The source of a strong ammonia smell that prompted the hazardous materials closure of a block of South B Street in San Mateo on Sunday morning has been identified by the San Mateo Consolidated Fire Department as a fluid leak from an unmaintained freezer.
The freezer was located in an apartment building at 1427 South B St., according to San Mateo police.
In a Nixle update at 9:45 a.m., the police department said:
“Officials have contained the source and cleared the scene.”