Police responded the 2000 block of Palm Avenue at around 10:35 a.m. where three brown bottles had been found at the rear of a building, one of them marked "cyanide," according to the San Mateo Police Department.
The area around the property was shut down to all traffic while a hazardous materials emergency protocol was carried out, led by the San Mateo Fire Department. No evacuations were necessary as officials quickly determined there was not an immediate threat to nearby tenants and residents.
The material in the bottles was analyzed and determined to be materials typically used for gold and silver-plating work, not cyanide, according to police. The bottles were collected for safe disposal, and the streets in the area were reopened to traffic at around 1:30 p.m.