Satellite imagery showed that China’s newest nuclear-powered attack submarine sank alongside a pier while under construction, a senior U.S. military official said Thursday.

The sinking of China’s first Zhou-class submarine represents a setback for Beijing as it continues to build out the world’s largest navy. Beijing has become increasingly assertive in pursuing its claim to virtually the entire South China Sea, which is crucial to international trade.

Meanwhile, China faces longtime territorial disputes involving others in the region including Brunei, Malaysia, the Philippines, Taiwan and Vietnam. The United States has sought to strengthen ties to its allies in the region and regularly sails through those waters in operations it says maintains the freedom of navigation for vessels there, angering Beijing.

The submarine likely sank between May and June, when satellite images showed cranes that would be necessary to lift it off the bottom of the river, said the official, who spoke on condition of anonymity to provide details about the submarine loss.

China has been building up its naval fleet at a breakneck pace, and the U.S. considers China’s rise one of its main future security concerns.

A Chinese Foreign Ministry spokesperson said Friday he was not familiar with the topic and did not provide any information when asked about it at a Beijing press conference.

The U.S. official said it was “not surprising” that China’s navy would conceal it. The submarine’s current status is unknown.

The identification of the sunken nuclear submarine was first reported by The Wall Street Journal. Thomas Shugart, a former U.S. Navy submariner and an analyst at the Center for a New American Security, first noticed the incident involving the submarine in July, though it wasn’t publicly known at the time that it involved the new Zhou-class vessel.

Satellite images from Planet Labs PBC analyzed by The Associated Press show what appears to be a submarine docked at the Shuangliu shipyard on the Yangtze River before the incident.

An image taken June 15 appears to show the submarine either fully or partially submerged just under the river’s surface, with rescue equipment and cranes surrounding it. Booms surround it to prevent any oil or other leaks from the vessel.

A satellite image taken Aug. 25 shows a submarine back at the same dock as the submerged vessel. It’s not clear if it was the same one.

It remains unclear if the affected submarine had been loaded with nuclear fuel or if its reactor was operating at the time of the incident. However, there has been no reported release of radiation in the area in the time since.

China as of last year operated six nuclear-powered ballistic missile submarines, six nuclear-powered attack submarines and 48 diesel-powered attack submarines, according to a U.S. military report.

News of the submarine’s sinking comes as China this week conducted a rare launch of an intercontinental ballistic missile into international waters in the Pacific Ocean. Experts say it marked the first time Beijing had conducted such a test since 1980.

Defense Secretary Lloyd Austin was in London this week to discuss progress made by the U.S., Britain and Australia toward their shared goal of deterring China’s increasingly assertive actions in the Indo-Pacific. The London summit is the third Defense Ministerial for the allies’ trilateral AUKUS partnership, and according to defense officials, it will see them look at the two key elements or pillars of their work together to increase security in the Indo-Pacific. 

The first of those pillars is helping Australia acquire nuclear-powered submarines, and the second is collaborating on emerging military capabilities.

Earlier this year, the partnership announced that Japan would work with AUKUS on maritime autonomy and, according to the official, there are also conversations with Canada, South Korea, and New Zealand about potential projects on emerging capabilities. 

China has accused AUKUS of provoking a nuclear arms race and disrupting peace and security in the Indo-Pacific region. 

contributed to this report.

Rep. Debbie Dingell believes her state will remain competitive until the last vote is counted on Election Day. 

“I don’t think we know who’s going to win Michigan yet,” the Michigan Democrat told chief Washington correspondent Major Garrett on “The Takeout” podcast.

Dingell said in 2016, she had a sense that Donald Trump would win her state, but that’s not the case this year. 

“I don’t think either of the candidates has won Michigan yet,” Dingell said. She noted that during his first run for president, Trump connected with auto workers and union workers. 

“He understood their fear and anxiety that their jobs had been shipped overseas,” she recalled. “Our supply chain had totally been shipped overseas.”

Much as it was in 2016, “this election is going to be about the economy,” Dingell said. She added the issues that people discuss around their kitchen table — like grocery prices, mortgage and rent payments, and college affordability — “all of those are the kinds of issues…we’ve got to be addressing.”

Dingell has some advice for Vice President Kamala Harris about how to win over Michiganders.  

“Let her be herself. Get out there,” Dingell said. “Get out to union halls. Talk to the people.” Dingell added that while she has a strong relationship with the Clintons, they did not take her advice in 2016. “I loved Bill and Hillary. You know that. They were friends,” she said. “They said they should have listened to me later,” particularly on talking to union members. 

This isn’t the case with the Harris campaign. “They listen to me,” Dingell said, noting that Harris traveled to Michigan on Labor Day.

While the congresswoman feels Michigan could go either way in the presidential race, she predicts Democrats will win the House back from Republicans in November.

“There are a lot of close seats, but I think we’re doing a very good job of defining what’s at stake,” Dingell said. “I think it’s going to be close…But I think quite frankly, the Republicans’ inability to get a lot of work done in the last two years has a lot of people willing to look and say what’s at stake.”

Dingell told Garrett that Harris has come to her on a regular basis to hear about the concerns of her constituents, not just since Harris became the candidate, but she also sought Dingell out when she was a senator. “She wanted to understand the auto industry. She wanted to understand the union workers. And quite frankly, one of the other subjects she has talked to me about frequently…is the different ethnic backgrounds, the cultural issues of a state like Michigan, which has a rich cultural diversity.”

One of the most pressing issues for Dingell is the Middle East conflict. She says the communities in her district and her state have large Jewish and Muslim populations, particularly of Palestinian and Lebanese descent. Dearborn, Michigan, became the first Arab-majority city in the United States in 2023.

“We need peace,” Dingell said. “And we’re seeing an escalation. It’s getting worse. The Jewish community is so worried about anti-Semitism and hate, but so is the Muslim community about [Islamophobia]. It’s real for both of them.”

Dingell said she’s had many conversations with both President Biden and Harris about what people in her communities who have lost family members and loved ones are saying about the conflict in the Middle East, and the need for a ceasefire.

“People need to understand how hurting people are, how this war in the Mideast, which has been going on for centuries, is very real in our own communities,” Dingell said. “We need peace. We need a ceasefire. We need no one else to die. And somehow, as elected officials, we need to somehow find a way to bring people together, not keep putting kerosene on a fire that is very dangerous to world peace.”

Executive producer: Arden Farhi

Producers: Jamie Benson, Jacob Rosen, Sara Cook and Eleanor Watson

CBSN Production: Eric Soussanin 
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Vice President Kamala Harris is set to visit Douglas, Arizona, on Friday, marking her first trip to the U.S.-Mexico border since becoming the Democratic presidential nominee. Harris will deliver remarks to call for tougher border security measures as part of her efforts to address border issues, according to a senior campaign official. 

Harris plans to say that American sovereignty requires setting rules at the border and enforcing them, stressing that Border Patrol agents need more resources.

The vice president will make combating the flow of fentanyl a focal point of her remarks and refer to it as a “top priority” for her presidency. Harris will propose adding fentanyl detection machines to ports of entry along the border and will call on the Chinese government to crack down on companies that make the precursor chemicals utilized in the making of fentanyl. 

While Harris will stress the need for border security and address the lack of current resources, the vice president will also advocate for an immigration system that is “safe, orderly and humane” according to campaign officials granted anonymity to speak freely on the prepared remarks. 

As Harris is set to make her case on the border, the Biden administration will soon move to cement the asylum restrictions it enacted at the southern border over the summer, officials told CBS News. The planned amended proclamation would make it less likely for the asylum restrictions to be lifted in the near future, according to two U.S. officials who requested anonymity to discuss internal government plans. Officials have credited the stringent measure for a sharp drop in illegal border crossings in recent months.

Harris’ first border trip as the Democratic nominee comes as the vice president is looking to make gains on her opponent, former President Donald Trump, on border issues. According to a recent CBS News poll, 58% of likely voters consider the U.S.-Mexico border a major factor in deciding who they will vote for. The poll also found 53% of likely voters would support Trump starting a national program to find and deport all immigrants who are in the U.S. illegally. 

Trump and Republicans have long campaigned on the need for strong border security and have attempted to place blame on Harris for the influx of illegal crossings during the Biden administration. 

During a Thursday press conference in New York, Trump denounced Harris’ border visit, telling reporters “she should save her airfare.”

“She should go back to the White House and tell the president to close the border,” Trump said. “He can do it with the signing of just a signature and a piece of paper to the border patrol.”

Harris will argue, according to a senior campaign official, that Trump was responsible for scuttling a bipartisan border bill that would have enacted permanent asylum restrictions and authorized additional border agents and resources. Trump urged his allies in Congress to reject the bill earlier this year.

“The American people deserve a president who cares more about border security than playing political games,” Harris plans to say, according to excerpts previewed by CBS News.

While Harris has been pushing for Congress to pass the bill from the campaign trail, Trump on Thursday referred to the legislation as “atrocious.”

“It would allow people to come in here at levels that would be incredible and would allow them to get citizenship” Trump told reporters. “It was not a border bill. It was an amnesty bill.”

The measure that failed to garner enough support from Senate Republicans in the spring also included executive authority to turn away migrants during spikes in illegal immigration and would have expanded legal immigration levels. 

contributed to this report.