Three teenage girls crossing a bridge in central Florida were killed by a freight train as they desperately tried to get out of its way and their helpless friend on the other side could only watch, police said Sunday.

The girls and the fourth teenager, a boy, were hanging out in Melbourne's downtown area — known for its shops and nightclubs — when they decided to cross the trestle around 6:30 p.m. Saturday, Lt. Curtis Barger said.

"The male made it across the tracks, turned around, heard the train, saw it and yelled for them to run," Barger said. "He then told them to jump."

The girls did not have enough time. Barger said all the teens were from the area, but their identities have not been released. That likely won't happen until Monday, after officials can compare dental records, he said.

John Vallee, 54, lives near the trestle that spans the Crane Creek and was watching TV when he heard a loud screech. He went outside and first thought he saw a blanket tangled under a rail car. Then he realized it was a person.

"It's going to be hard for me to get to sleep," Vallee told Florida Today. "I can't get it out of my mind."

Barger said the teens' parents dropped them off at a Melbourne mall and the kids took a bus downtown, where they were "just goofing off."

"It's very tragic," he said. "Especially because it's young folks who haven't had a chance to experience life, it's exceptionally touching."

Authorities in Melbourne, a city of about 77,000 nearly 50 miles east of Orlando, are investigating.

The track is owned by the Florida East Coast Railway, which operates about 350 miles of track along the state's east coast. Railway officials did not immediately return calls for comment.