Cows so sick that they are unable to stand have reportedly been slaughtered and sold with little or no veterinary inspection in Poland.

An undercover video reportedly shows extremely sick cows being dragged out of trucks and into the slaughterhouse in the central Polish region of Mazovia. The country is one of Europe’s biggest meat exporters.

As reported by the Guardian, the video appears to show workers at the slaughterhouse removing evidence from the carcasses such as pressure sores and tumours that indicate that the cows have been sick and lying on their side for days on end.

Experts who have seen the film said it raises the possibility of serious health risks, and called on the Polish government to act quickly to notify all other European states.

Chris Elliott, professor of food safety at Queen’s University in Belfast and founder of the Institute for Global Food Security, told the Guardian: “If there is any evidence at all that some of this meat has left Poland then there will be the potential for a European-wide safety alert, with the involvement of many regulatory agencies and potentially police forces from across Europe.”

According to Patryk Szczepaniak, the reporter who worked at the slaughterhouse and recorded the footage, instead of being inspected by qualified veterinarians as the law demands, the carcasses would simply be marked as safe for human consumption by staff.

“I was ordered by my supervisors to mark the meat as healthy, and basically to make it prettier. It was horrible, believe me. The smell of rotting meat just makes you puke. I had to make it prettier by scrubbing it with my knife.”

According to the Guardian’s report, meat that receives certification will not be inspected before it is sent to suppliers and on to consumers, including in other countries. Approximately 80% of the beef produced in Poland is sent for export.

In December, the owner of a slaughterhouse near Łódź in central Poland was given a prison sentence for running a similar operation (he has appealed against his sentence). Prosecutors are also conducting an investigation into a slaughterhouse in eastern Poland.

Responding to the airing of the secret video on Polish TV on January 26, Paweł Jakubczak, the head of the Mazovian region’s veterinary inspectorate, announced that the slaughterhouse’s designated veterinarian and his supervisor at the county level had both been dismissed, and that the police had already begun investigations.

“I think the police, which is at this moment already engaged in this issue, will be trying step by step to explain what has been the role of the supervisory authorities in this illegal, reprehensible and downright criminal procedure.”