FREMONT, Calif. (AP) — The San Francisco Bay Area Tesla factory where three workers were burned by hot metal was previously cited for a safety violation.

Records indicate the California Division of Occupational Safety and Health fined Tesla $2,700 last year for a serious violation at the Fremont factory that was uncovered during an accident investigation.

Cal-OSHA spokesman Peter Melton said investigators found a hydraulic power press did not have a proper stop control. At least one person was injured, but Melton did not know the extent of the injuries.

Tesla was also fined for an accident at a different Bay Area facility two years ago in which a worker lost a fingertip.

Two of the three workers injured when a machine malfunctioned at the factory on Wednesday remained hospitalized on Thursday. One suffered serious injuries, and the other two had minor injuries.