DUBLIN -- The Dublin/Pleasanton station has reopened after investigation of a possible natural gas leak, officials said.

The station was closed at 11:55 a.m. and trains were turned around after a heavy natural gas smell was detected, according to BART spokeswoman Alicia Trost.

At 12:11 a.m., the Livermore Fire Department determined the station was safe and it was reopened.

The cause of the smell is unknown. A nearby construction site will be investigated by PG&E, Trost said.