The police bomb squad has been called to the University of Western Australia after reports of a toxic acid spill in the zoology department at its Crawley campus.

Department of Fire and Emergency officers set up a 200 metre exclusion zone around the Hackett Drive building at 11.30am on Wednesday, amid concerns of a suspect container of acid discovered during a routine audit.

Fire units at UWA following a chemical scare. Credit:Channel 7

A DFES spokeswoman said five fire and rescue crews had responded to the incident and the police bomb squad had been called in to safely remove the noxious substance.

It has been reported that the substance was picric acid, which is often used in solutions to preserve plant and animal tissue. It is also an explosive.