Metrolink Train (Creative Commons)

The Los Angeles-bound train was traveing from Oceanside under the Alicia Parkway overcrossing when it struck the teens at around 6 a.m.

Investigators are unsure why the teenagers were on the tracks at the time of the accident, but they suspect the victims may have been sleeping on the tracks.

According to Metrolink spokesperson Angela Starr, the surviving teenager heard the train and was barely hit as she moved out of the way. She suffered moderate injuries while the other two bodies were dragged about a quarter of a mile down the tracks.

Having reportedly met through Facebook last week, the two females and one male had, “met up earlier in the evening, went to Laguna Beach and ended up at this popular 'hang out' spot," said Orange County Sherriff’s spokesman Jim Amormino.

Amormino also mentioned that the surviving woman passed a sobriety test at the scene. Further information will be gathered from autopsies to determine whether or not the other teens were under the influence of drugs or alcohol.

This incident brings to attention recent problems that Metrolink has experienced with people trespassing onto tracks, Starr said.

Keith Ball, a resident of the area, said teenagers commonly gather near the tracks to hang out.

"It’s been going on all summer," he said. "It’s a problem. They really need to come down here and patrol this area more."

According to Starr, the train’s crew and 67 passengers were not injured and investigators will review footage taken by the train’s camera.

Authorities closed the tracks for further investigation, causing a delay for other trains and temporarily shutting down service between Irvine and San Diego.

Reach reporter Marlise Knechtle here.

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