The MacArthur BART station was closed briefly Saturday night after a chemical gas was released on a train, BART officials said.
BART police responded around 7 p.m. to a reported fight on a train at the station, BART spokesman Jim Allison said.
While police were removing the involved parties from the train, someone released pepper spray or some other chemical irritant. The gas spread into the station area, prompting police to shut it down.
The gas cleared quickly, however, and the station was reopened within about 11 minutes, Allison said. The entire incident was cleared by about 7:20 p.m.
No arrests were made in connection with the fight.