BELMONT — As the warning lights flashed and the safety gates went down at the Brighton Street commuter rail crossing Friday morning, horrified bystanders watched in disbelief as a train barreled down on the car sitting trapped on the tracks.
Cars began honking, and two boys — aged 11 and 10 years old — fled from the car. But a 6-year-old boy was still inside, officials said. The driver, a 58-year-old woman, rushed to get him out, but it was too late.
The inbound Fitchburg Line train crashed into the back of the car, sending it spinning into the woman, who was seriously injured. The little boy inside was safe.
“We don’t want anyone to jump to a conclusion as to how this happened,’’ Transit Police Superintendent Richard Sullivan told reporters at a briefing Friday. “I have a 7-year-old daughter myself. This is a very tragic situation, and our thoughts and prayers are with everyone who was in this vehicle, particularly the female operator.’’
The woman was taken to Beth Israel Deaconess Medical Center, Sullivan said. The boys were uninjured, but were taken to a Boston hospital for observation.
The woman is the mother of the 11-year-old boy, Sullivan said, and the two other passengers were brothers. All three are classmates, he said, though he did not identify the school they attend or say whether they were en route to it.
At the time of the 8 a.m. accident, Sullivan said, the lights, horn, and gates were functioning at the crossing. How and why the woman’s car was on the tracks even though the safety controls were operating is under investigation, he said. Witnesses said the woman appeared to have been hemmed in by traffic.
According to Keolis spokesman Leslie Aun, trains are authorized to travel through the Brighton Street crossing at 75 miles per hour. Sullivan said the investigation will determine how fast the train was traveling at the time of the impact.
The train’s operator “did try to stop,’’ said Sullivan.
“I give a lot of credit to that conductor,” said Mike Bennett, who was working in a nearby plumbing supply company when he heard a lot of honking and ran to the window. “He slowed considerably.”
Bennett said the woman driver appeared frantic, as if she was trying to get someone out of the car. People were running to help, he said, but it happened so fast that no one was able to reach her.
Heidi Cho, who was waiting for a bus about 100 feet away, said she saw children run from the car as the train approached.
The train blew its horn, said both Cho and Bennett, but could not stop altogether.
The train hit the car with a bang, Bennett said, spinning it so hard it wound up facing the other way on the other side of the street. He couldn’t see the woman anymore and thought at first that she had been killed.
“I was baffled. I was, like, ‘Oh my God, did that just happen in front of me?’” He said. “It seemed like a scene out of a movie.”
He said there was heavy traffic at the time of the accident, and there were cars in front of and behind the woman’s car on either side of the gates.
“It shook me up,” he said.
Karl Redgate, a passenger in the third car of the train, said no one on board felt any sort of impact.
Redgate said a conductor announced to passengers that the train had hit a car, and the passengers remained on the train until about 8:45 a.m.
Aun said about 500 passengers and crew were on board Train 408 during the crash; none was injured.
Images and footage from the scene:
John R. Ellement of the Globe staff and Globe correspondent Dylan McGuiness contributed to this report. Evan Allen can be reached at evan.allen@
globe.com. Follow her on Twitter @evanmallen. Olivia Quintana can be reached at olivia.quintana
@globe.com. Follow her on Twitter @oliviasquintana.