Published: Jul 15, 2014 10:37 AM EDT
Updated: Jul 15, 2014 12:06 PM EDT

MOSCOW (AP) - Investigators now say it wasn't a power surge that caused this morning's deadly subway train derailment in Moscow.
The derailment, deep below the city's streets, left at least 20 people dead and sent 150 others to the hospital -- many with serious injuries. The dead and injured had to be removed from twisted and mangled cars, which had been crowded with passengers at the height of the morning rush hour.
Officials had said earlier that a power surge triggered an alarm, causing the train to stop abruptly. They now are looking at whether there was a problem in one of the cars, or whether the roadbed had sunk.
Moscow's airports and transit systems have been a prime target for terrorists over the past two decades, but officials are vigorously dismissing terrorism as a possible cause.
In a video released by emergency officials, several wrecked train cars appeared to be almost coiled, occupying the entire width of the tunnel. Workers were trying to force open the mangled doors of one car to retrieve bodies. Survivors, meanwhile, walked along the tracks in the dimly-lit tunnel.
Technical glitches occur regularly in the Moscow Metro, but the system hasn't seen deadly accidents in decades.
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158-c-17-(Jim Heintz, AP correspondent)-"investigate what's happening"-AP correspondent Jim Heintz reports that the derailment is in a tunnel that's far from the surface. (15 Jul 2014)
CUT *158 (07/15/14)££ 00:17  "investigate what's happening"
157-c-19-(Jim Heintz, AP correspondent)-"of terrorist act"-AP correspondent Jim Heintz reports that a subway train has derailed in Moscow, causing multiple deaths and injuries. (At latest count 20 had died and more than 150 were injured; watch for updates.) (15 Jul 2014)
CUT *157 (07/15/14)££ 00:19  "of terrorist act"
APPHOTO XAZ117: Paramedics and firefighters carry an injured man out of a subway station after a rush-hour subway train derailment in Moscow, Russia, Tuesday, July 15, 2014. A rush-hour subway train derailed in Moscow Tuesday, killing 20 people and injuring at least 150, emergency officials said. Several cars left the track in the tunnel after a power surge triggered an alarm, which caused the train to stop abruptly. (AP Photo/Ivan Sekretarev) (15 Jul 2014)
APPHOTO XAZ117 (07/15/14)££

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