Driver of California Tour Bus May Not Have Braked Before Hitting Tractor Trailer, Officials Said

iStock/Thinkstock(DESERT HOT SPRINGS, Calif.) — The driver of the California tour bus that killed 13 passengers and injured 31 others Sunday may not have stepped on the brakes before the bus plowed into another vehicle, officials said Monday.

There was no indication of breaking by the bus, California Highway Patrol Border Division Chief Jim Abele told reporters at a press conference.

The bus, which was on Interstate 10 returning to Los Angeles from Red Earth Casino in Thermal, California, crashed into a tractor trailer, leaving the front of the bus demolished, Abele said Sunday. Officials said the bus had arrived at the casino Saturday night between 11 p.m. and 11:30 p.m. and left Sunday at 4 a.m. The bus did not have seat belts.

It was also revealed Monday that the bus driver may have been inside the casino during that time frame.

The investigation remains in a very early stage, officials said, adding that it’s too early to say what caused the accident.

“The speed of the bus was so significant that when it hit the back of the big rig, the trailer itself entered about 15 feet into the bus,” Abele said Sunday.

The National Transportation Safety Board, who is investigating the crash, asks that witnesses call the California Highway Patrol.

The bus had been inspected three times since 2014 and no mechanical issues were found, Abele said Sunday.

Copyright © 2016, ABC Radio. All rights reserved.