Officials say that 27 Polish police officers have been hurt — not in any engagement with criminals, but by ticks that have invaded their police station.

The ticks were carried by pigeons that nested on ledges outside the windows of the headquarters in Poznan, a city in western Poland.

Andrzej Borowiak, the police spokesman for the region, said that 27 officers reported having red marks on their bodies that suggested that they had been bitten by the ticks. They are receiving medical treatment for their bites.

Images broadcast Tuesday by the TVN24 broadcaster showed firefighters using special equipment to disinfect filthy window ledges covered in pigeon droppings.