A 13-year-old was behind the wheel of one of the vehicles involved in an accident that killed nine people in the US state of Texas.
The teenager was driving a pickup truck that crashed into a van, the US Transportation Safety Administration (NTSB) said on Thursday.
Investigators assume that a tire of the small truck burst before the collision.
The teenager, the 38-year-old passenger and seven passengers on board the van died in the serious accident on Tuesday near the city of Midland.
The golf team from a university was traveling in the van.
The coach and six team members were killed.
They were returning from a golf tournament.
The NTSB believes the teen pulled the pickup truck into the opposite lane after the tire blew out.
"It was a high-speed head-on collision," said Bruce Landsberg of the NTSB.
However, he could not say in the same way whether someone had been traveling too fast.
The burst tire was a spare tire.
Two members of the golf team were still being treated in hospital as of Thursday.
In Texas, youngsters can start driving lessons at 14, but don't apply for a novice driver's license until they are 15.