Employees at the Coca-Cola plant in Needham Heights were evacuated Wednesday evening after there was an ammonia leak in the building's compressor room.

Needham Police and Fire responded to a call at the plant, located at 9 B St., at around 6:55 p.m. on Oct. 31. A HAZMAT team and the Needham Board of Health were also called in. All employees at the plant were evacuated as a precaution.

"After conducting several tests of the building, the HAZMAT team determined there were no traces of ammonia in the air, and all employees were then allowed to return," Needham Police Lt. Chris Baker said in an email.