WASHINGTON — A supervisor says the engineer in a deadly train crash last September was warned twice about cell phone use while on duty. Despite that warning, the engineer sent and received 43 text messages and made four phone calls the day of the collision, federal records show.

The crash in California last year killed 25 people and injured at least 130 people.

Federal investigators on Tuesday released the transcript of text messages sent and received by engineer Robert Sanchez as the National Transportation Safety Board opened a two-day hearing on the train crash. The board is not expected to issue a final report for a few months.

Investigators sketched out the days and minutes leading up to the crash between the Metrolink train and a Union Pacific freight train that ended up on the same shared track and slammed head-on at about 40 mph.

The panel was to hear from union officials as well as the Federal Railroad Administration on Wednesday.

Sanchez was killed in the collision.

Text messages indicated he had allowed a teenager to ride in the cab several days before the crash, and that he was planning to let him run the train between four stations on the evening of the crash.

"I'm gonna do all the radio talkin' ... ur gonna run the locomotive & I'm gonna tell u how to do it," Sanchez wrote in one text four days before the crash.

Officials with Connex Railroad LLC, the contractor that provides engineers who run Metrolink trains, said the company had a strict policy against use of cell phones. When that policy went into effect in September 2006, officials stopped and boarded trains to monitor their employees' cell phone use.

Rick Dahl, a representative of Connex, described an incident in which a fellow company manager called Sanchez's cell phone — which rang as Dahl was interviewing him.

"I told the engineer that he was in violation of our policy and that I was going to take an exception to that," Dahl said. "The engineer told me that he knows the policy and that he forgot to turn it off when he stowed it away in the morning."

The second warning came in early August 2008, Dahl said, after the train's conductor said he had seen Sanchez using a cell phone on the job. Dahl said he reiterated to Sanchez the company's policy on cell phone use.

During the hearing, the NTSB panel also focused on the operation of trackside signals designed to prevent collisions, as well as compliance with safety procedures — namely, letting unauthorized individuals into the cab.

Investigators said there were no signs of any mechanical problems with either train.