The leak was reported at the refinery on East Pacific Coast Highway at about 6:39 a.m., according to a Fire Department release. One person was rescued by firefighters using a rigid basket or stretcher and lowered by a rope system to the ground.
The gas was reported to be hydrogen sulfide and butane. Three of the people were listed in moderate condition and one was in serious condition.
The risk from the gas has since been mitigated and there’s no further hazard to people in the area, according to the Fire Department.
Marathon confirmed four employees were hospitalized after they were exposed, according to news reports.
The company didn’t immediately respond to a request for more information.
In 2020, a fire triggered by an explosion broke out at a Marathon refinery in Carson in a section of the plant that had been cited by California inspectors for workplace safety violations. No one was injured in the fire.