Romans said the San Rafael Fire Department responded to a fire coming out of a street grate near the 1800 block of Fourth Street around 6:30 p.m. Wednesday.
PG&E crews arrived at 7:30 p.m. in response to the odor of gas and remained at the site overnight, Romans said.
At around 4:15 a.m. today a gas pipe ruptured and the San Rafael Fire Department responded at 4:30 a.m., Romans said. The three-story building was evacuated and Fourth Street was closed around 5:15 a.m., Romans said.
Romans said the leak happened at a connection between a 6-inch steel pipe and a 4-inch plastic pipe. The cause of the leak is under investigation but Romans said connection points between steel and plastic pipes sometimes become weak spots.
Romans said the evacuated occupants were allowed back into the building around noon. PG&E crews will be repairing the sidewalk in the area of the gas leak and will be on the site until around 9:30 p.m., Romans said.
The two westbound lanes of Fourth Street are closed and traffic is using the two eastbound lanes, Romans said.