British authorities launched a criminal investigation Friday into a contractor’s stockpiling of hundreds of tons of medical waste, including amputated body parts.

The situation prompted an emergency meeting of COBRA, the British government’s crisis response committee, last month amid fears the backlog could pose a public health hazard.

Britain’s Environment Agency said Friday that the contractor Healthcare Environmental Services (HES), which is responsible for destroying medical waste from hospitals in England and Scotland, had breached its permits at five sites for not disposing of waste quickly enough. At one of the company’s disposal plants in Yorkshire, there was 350 tons of waste in September, including amputated limbs and toxic waste from cancer treatment — five times over the permitted level.

“We are taking enforcement action against the operator, which includes clearance of the excess waste, and have launched a criminal investigation,” the agency said.

The contractor, HES, blames its failings on a reduced capacity in the country’s incineration facilities, as a result of aging infrastructure, leading to lengthy breakdowns. It said the reduced capacity had been obvious over the past year and had affected all players in the industry.

The company, which described itself on its website as “the UK’s leading independent provider of healthcare waste management” is now trying to ship 750 tons of the waste to the Netherlands for processing.

The breaches were revealed in official documents leaked to the Health Service Journal and came after the Environment Agency reportedly served the contractor with more than a dozen enforcement notices over the issue.

“This anatomical waste, which is made up of human body parts and surgical waste, has now been placed in fridges,” the website reported.

While the government is insisting there has been no risk to public safety as a result of the backlog, politicians are questioning the way it has been handled and whether it could have broader environmental implications.

“This was serious enough to have a criminal investigation and serious enough to go to a COBRA meeting, and yet there was no statement to parliament or to the local community,” said opposition Labour MP Yvette Cooper.

Jonathan Ashworth, Labour’s health spokesman, also slammed the government for not disclosing the issue. “These are staggering revelations and given the number of NHS trusts involved, along with wider environmental health implications, I’m disappointed the health secretary didn’t inform parliament last month,” he said.

A leaked National Health Service document report warns that if HES goes under as a result of the scandal, there could be a knock-on effect for the disposal of medical waste across the country. But the government says it has put contingency plans in place, and allocated £1 million to hospitals to address the issue.

“We are monitoring the situation closely and have made sure that public services — including NHS trusts — have contingency plans in place,” said a government spokesman. “There is absolutely no risk to the health of patients or the wider public.”