Thirteen children under the age of 14 died in central Mexico and authorities said they suspect contaminated IV feeding bags as the culprit.

The federal Health Department ordered doctors across Mexico to not use IV feeding bags by the company Productos Hospitalarios S.A de C.V., after an apparent outbreak of the multidrug-resistant bacteria known as Klebsiella oxytoca.

The bacteria were first detected in November at three government hospitals and one private one in the State of Mexico, on the outskirts of Mexico City, officials said Thursday.

To date, there have been 20 cases of possible infection of which 15 were positive for the bacteria, officials said. The bacteria was ruled out in one case and is suspected in four of them.

Of the 19 patients, 13 died and six others are being treated at hospitals. The health department said the children appeared to have died from a blood infection.

“This outbreak is preliminary linked to intravenous parenteral nutrition solutions or to the supplies used for their application that could be contaminated,” the health department said in a statement, adding that the exact source of the infection is still under investigation.

Asked about the cluster of cases, President Claudia Sheinbaum said Thursday that health officials “told me about a case yesterday, but let’s say, it’s under control.”