REUTERS - Twelve people were killed on Tuesday and up to 120 injured when a Moscow underground train derailed between two stations during the morning rush hour, the Emergencies Ministry said.
Russia's investigative committee said it was looking into the causes of the accident. There seemed to be no suggestion of foul play.
Injured passengers were carried on stretchers, bloodied and bandaged, out of metro stations and helicopters ferried the most seriously hurt to hospital. Passengers looked stunned or were crying after being helped to the surface by emergency services.
"So far 12 people are dead," an emergency ministry official told reporters at the scene.
Investigators said a power surge caused the train to stall and several cars to come off the rails between the Slaviansky Boulevard and Park Pobedy stations.
"It braked very hard. The lights went off and there was lots of smoke," a man, his nose bloodied, told Rossiya-24 television.
"We were trapped and only got out by some miracle. I thought it was the end. Many people were hurt, mostly in the first rail car because the cars ran into each other."
A city transport services spokesman told news agency Interfax that all passengers had been evacuated from the affected stations by midday, dismissing reports that some passengers were still trapped in the underground tunnel.
The Moscow metro is the world's busiest, with as many as 9 million people on week days riding a system that is widely recognised for its reliability.
Famed for its high-vaulted halls adorned with Soviet socialist realist art, the underground network has expanded from 13 stations opened in 1935 to 194 stations across the megalopolis today.
Islamist militants have previously carried out deadly attacks in Moscow, including twin suicide bombings that killed 40 people on the subway in 2010.
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