Richard Vogel, Associated Press
Investigators photograph a mangled Metrolink commuter train in Chatsworth, Calif., on Sunday. Twenty-five people were killed in the Friday train crash.

LOS ANGELES — Federal investigators plan to subpoena the cell phone records of the engineer who is said to have been exchanging text messages in the minutes before his commuter train ran through a red signal and smashed into a freight train here Friday, killing 25 people.

Kitty Higgins, a member of the National Transportation Safety Board, which is leading the investigation, said Sunday that the agency would subpoena the records and also question the young men who told KCBS-TV that they had taken part in an exchange of text messages with the engineer just before the crash.

Whether the engineer, Robert Sanchez, who was killed, had been distracted is among the bevy of questions investigators are seeking to answer. Others include whether the three-car Metrolink train and track equipment were functioning properly and what role dispatchers controlling train traffic might have played.

In the deadliest train accident in the country in 15 years, the commuter train, headed from Union Station here north to the suburbs, collided head-on with a Union Pacific freight train during rush hour Friday near a residential area of the San Fernando Valley. The crash, which also injured 135 people, nearly obliterated the front car of the commuter train and trapped the living and the dead for hours.

Officials at Metrolink have said the engineer passed through a red signal without stopping, probably causing the accident.

But federal investigators cautioned against jumping to conclusions and predicted that the investigation could span many months.

Why the two trains were on the same track heading toward each other at about 40 miles per hour has puzzled officials. The claim of the text message exchange is among the more sensational factors officials are investigating.

KCBS-TV reports on Saturday quoted a group of young railroad buffs as saying they had a friendship with the engineer and displaying messages they said came from him immediately before the crash.

The last message, at 4:22 p.m., about a minute before the crash, tells one of the group that the engineer would be meeting another passenger train. It says, "yea ... usually (AT) north camarillo," apparently a reference to a town about 25 miles west of the crash site in the Chatsworth neighborhood in the San Fernando Valley.

One of the young men, Evan Morrison, would not comment Sunday and the others could not be reached or did not answer e-mail messages. Morrison is one of the more prolific within a group of rail devotees who post pictures of trains and other information on Web sites.

A friend of Sanchez put a video on YouTube that included images of him driving a train and the words, "Rob, from all us railfans, we love you."

Higgins of the safety board has said reports of a driver distracted by a cell phone had proved false this year in the case of a fatal trolley accident in Boston.

The state chairman of Brotherhood of Locomotive Engineers and Trainmen, the union representing Sanchez, said it remained to be determined why he would pass a red signal, whether a health problem disabled him or whether in fact the signal was red, as Metrolink insists.

"He was not crazy, I can tell you that," the union official, Tim Smith said. Smith described Sanchez as conscientious about safety, saying he complained to the union about missing or broken signal flags along his route.

"He has been proactive about calling attention to things," Smith said. "He was known as one of the better engineers for Metrolink."

As television trucks set up camp, no one answered the door at Sanchez's home, a one-story, bungalow-style house in La Crescenta, a middle-class suburb north of Los Angeles.

Anoosh Gharadaghian, 46, who has lived in the neighborhood for 10 years, said Sanchez had moved in two to three years ago with four dogs. Gharadaghian described him as reclusive, saying, "He did not introduce himself to the neighbors, and this is a neighborhood where everyone knows each other."

Sanchez appeared to be single and was occasionally visited by an elderly woman Gharadaghian said she assumed was his mother. Another neighbor, George Paijuk, 19, a freshman at Pasadena City College, said Sanchez was "a very secluded guy, even the neighbors didn't know him."

At the scene of the crash, work continued to clear the scattered seats, glass, metal and other debris as investigators took pictures and videotaped the remnants of the collision.

Utahn killed

The Associated Press list of victims includes Charles Peck, 58, of Salt Lake City. No other information was available Sunday night.