A search resumed Monday in the San Joaquin River for two people missing after a boating incident over the weekend.

A boat was involved in an incident shortly after 5 p.m. Sunday at Prisoner Point and Hayes Beach, the San Joaquin County Sheriff’s Office said.

Exactly what happened remains unclear, though officials say one boat overturned and sank with three people onboard.

One person was pulled from the water with major injuries and flown to a hospital in critical condition. The other two people remain missing.

Crews searched into the evening Sunday before suspending the effort because of darkness.

The sheriff’s office Dive Team joined the Boating Safety Unit on Monday as the search resumed.

Authorities have not released any other details about the incident, including exactly where on the San Joaquin River it happened.

The sheriff’s office said previous information it received and sent out regarding two boats being involved was incorrect.

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