Shasta County Sheriff’s Officer are worried a 12-year-old boy who was inner-tubing behind a boat on Lake Shasta was struck by the boat on Monday. The driver of the boat was a girl younger than 16.

Robert Noftz, 50, was supposed to be supervising the children, but he was later arrested for boating under the influence, KRCR News Channel 7 reports.

Sheriff's investigators believe the boy on the tube told the girl to try to knock him off the tube.

When she tried, the girl may have turned too sharply, hitting her own wake, sending the boat into a collision course with the boy.

KRCR reports the boy appeared to try jumping from the tube, but couldn’t in time.

When the boat hit the boy, he went under the water and didn’t resurface.

Sheriff’s investigators tell KRCR the boy’s life jack was found floating nearby. From the way it looked, the jacket may have been hit with the boat’s propeller.

Shasta County sheriff’s dive team has spent the past two days combing the lake near Digger Bay Marina.

Using side-sonar scanning on their boats, dive teams are hoping to identify anything resembling the boy. Sadly, their efforts have come back fruitless thus far.