Seven people, including a police officer, were stricken by an unknown substance in downtown Los Angeles Friday night and rushed to a hospital, but all were expected to be treated and released.

Firefighters responded about 7:15 p.m. to the intersection of San Pedro and Fifth streets after at least one person was stricken on a bus bench in the area, according to Jason Schutt of the Los Angeles Fire Department.

The patients were exposed to an unknown hazardous material and did not suffer drug overdoses as originally reported.

A crowd gathered at the intersection as firefighters tended to the victims and officers were summoned to provide crowd control, according to the Los Angeles Police Department.