Amagasaki, Japan ? The death toll rose to 73 today in Japan’s deadliest rail crash in decades as crews pulled more victims from the wreckage. Investigators focused on whether excessive speed or the driver’s inexperience caused the train to derail and slam into an apartment building.

The seven-car commuter train carrying 580 passengers left the rails Monday morning near Amagasaki, a suburb of Osaka about 250 miles west of Tokyo. It hit an automobile before plowing into the nine-story complex, injuring more than 440 people.

Rescuers worked through the day and used floodlights overnight to reach survivors and the dead. Early Tuesday, they pulled out a conscious but seriously injured 46-year-old woman, then a 19-year-old college student, also in serious condition.

Police said there a few other passengers were still trapped but no one was responding, an indication that there were no more survivors.

But most of the work early Tuesday was grim. Crews pulled 16 more bodies from the twisted rail carriages, pushing the death toll from 57 to 73.

Police said the 19-year-old student pulled from the debris, Hiroki Hayashi, had survived under the wreckage when rescuers managed to get him intravenous fluids, and hospital officials said he was in serious condition.

Earlier, Hayashi’s brother, Takamichi, said his older brother had called their mother after the crash from inside one of the train cars hours after the crash.

“He told my mother: ‘I’m in pain. I’m not going to make it,”‘ the brother said.

Two of the five derailed cars were shoved inside and flattened against the wall of the building’s first-floor parking garage.

A crowd gathers to watch firefighters try to rescue people trapped in train cars after a derailment at Amagasaki, near Osaka, Japan. The packed commuter train jumped the tracks Monday and hurtled into an apartment complex, killing at least 73 people and injuring more than 440 others.

Officials said no cause had been ruled out but added that investigators suspected speed and the driver’s experience. He’d been on the job less than a year.

The driver — identified as Ryujiro Takami, 23 — was unaccounted for.

He got his train operator’s license last May. A month later, he overshot a station and was issued a warning, railway officials and police said. Passengers said he also stopped too far past a station platform Monday just before the crash.

Tsunemi Murakami, safety director for train operator West Japan Railway Co., said that it had not been determined how fast the train was traveling at the time of the crash, 5:18 a.m. Monday.

A surviving crew member told police he “felt the train was going faster than usual,” public broadcaster NHK said.

That echoed comments from passengers who speculated the driver might have been speeding to make up for time lost when he overshot the previous station by 25 feet and had to back up. The train was nearly two minutes behind schedule, media reports said.

The crash occurred on a curve with a speed limit of 43 mph. Murakami estimated the train would have had to be traveling at 82 mph to have jumped the track purely because of excessive speed.