PITTSBURG (CBS SF) — Police activity due to reports of shots fired on the platform at the Pittsburg/Bay Point BART station caused a major delay on the system Monday evening, BART officials said.

The major delay was present on the Antioch line in the Antioch and SFO/Millbrae directions. The Pittsburg/Bay Point station was closed briefly and trains were holding there, but the station reopened at 7:20 p.m.

Five people were detained at the station by BART police following the investigation, BART said on Twitter. There were no injuries reported.