Three people suffered minor injuries when a 300-ton crane tipped over at the ExxonMobil refinery in Torrance on Monday morning, firefighters said.
The collapse took place about 9:30 a.m. as the crane was moving some sort of debris, according to the Torrance Fire Department.
Crews were looking into the possibility of a flammability issue with the collapse.
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The refinery said in a statement that there was "no impact to the community."
The 750-acre refinery, located about 20 miles south of downtown Los Angeles, employs about 650 people, according to ExxonMobil. The plant processes an average of about 155,000 barrels of crude oil per day.
The refinery was largely out of operation until earlier this year due to a February 2015 explosion that caused extensive damage to the facility and injured four people. Federal authorities blamed a breakdown in safety procedures for causing the 2015 explosion.