LOS ANGELES (AP) - The death toll from the head-on collision of a commuter train and freight train rose Saturday as crews retrieved an 18th body and said they could see several more in the wreckage of the deadliest U.S. passenger train accident in 15 years.
Officials said they didn't yet know why the Metrolink commuter train and the freight were on the same track in suburban Chatsworth.
Deputy Fire Chief Mario Rueda said the chance that anyone was still alive in the wreckage was "very remote."
The last survivor was pulled out Friday evening, said fire Capt. Armando Hogan.
"Words can't explain or in any way console those who have lost loved ones, those who at this moment still don't know what the condition or status of their loved ones is," Mayor Antonio Villaraigosa said at a news conference. "I can only tell you that these firefighters and police officers have worked feverishly through the night."
The mayor reported the 18 confirmed deaths, and Los Angeles County coroner's Assistant Chief Ed Winter said that count did not include several bodies that could be seen but hadn't been reached in the lower level of a mangled double-decker Metrolink passenger car.
A total of 135 people were injured, with 81 taken to hospitals, the mayor said. Many were in serious or critical condition.
Worried relatives and friends gathered at nearby Chatsworth High School to wait for news as rescue workers delicately dismantled the passenger car.
Debra Nieves was concerned about her sister, Donna Remata, 49, who worked in downtown Los Angeles.
"That was her train and she's not home," said Nieves, 41, of Long Beach. "But until I find out for sure that they found her, I'm not going to leave."
The impact rammed the Metrolink engine backward into a passenger car, which rested on its side with the engine still inside it early Saturday, and accordioned the freight train cars. Two other Metrolink cars remained upright. Crews had to put out a fire under part of the train.
Bulldozers were used to raise the commuter train's engine and timbers were slid beneath it as firefighters worked to free a body pinned under the engine.
Fire Capt. Steve Ruda said the goal was to eliminate every piece of metal and gradually work into the passenger spaces of the double-decker rail car.
"There's human beings in there and it's going to be painstaking to get them out," Ruda said. "They'll have to surgically remove them."
His firefighters had never seen such carnage, he said.
"It's the worst feeling in the world because you know what you're going to find," said fire Capt. Alex Arriola, who had crawled into the bottom of the smashed passenger car. "You have to put aside the fact that it's someone's husband, daughter or friend."
Officials said there were 222 people on the Metrolink train and three Union Pacific employees aboard the freight train.
Asked how the two trains ended up on the same track, Steven Kulm, a spokesman for the Federal Railroad Administration, said: "We are nowhere near having any information on that."
Kulm said the federal investigation will be headed by the National Transportation Safety Board, while his agency will review whether any federal rail safety regulations were violated.
Union Pacific spokeswoman Zoe Richmond said it is common in California for freight and commuter trains to use one track.
Metrolink spokeswoman Denise Tyrrell said the Metrolink train left Union Station in downtown Los Angeles and was headed northwest to Moorpark in Ventura County. The trains collided at about 4:30 p.m. in the Chatsworth area of the San Fernando Valley, near a 500-foot-long tunnel underneath Stoney Point Park.
There is a siding at one end of the tunnel where one train can wait for another to pass, Tyrrell said.
"I do not know what caused the wreck," said Tyrrell who broke down crying and was shaking. "Obviously two trains are not supposed to be on the same track at the same time."
Until Friday, Metrolink's worst disaster was on Jan. 26, 2005, in suburban Glendale when a man parked a gasoline-soaked SUV on railroad tracks. A Metrolink train struck the SUV and derailed, striking another Metrolink train traveling the other way, killing 11 people and injuring about 180 others. Juan Alvarez was convicted this year of murder for causing the crash.
That was the worst U.S. rail tragedy since March 15, 1999, when an Amtrak train hit a truck and derailed near Bourbonnais, Ill., killing 11 people and injuring more than 100.