Sixty-six buses, 40 ambulances and eight helicopters have been deployed by rescuers for evacuations. Volunteers helped to get the injured out of the tunnel. The driver of the derailed train is being treated in the hospital, Moscow authorities say. A power failure, a botched emergency stop or a mechanical flaw with a wheel chassis are suspected to be at the origin of derailment but nothing is for sure, for the instant. Terrorism was excluded by the officials. “No signs of terrorist act are being seen. It’s most likely a technological accident,” said the spokesman for the Russian Investigative Committee, Vladimir Markin. The derailing closed one of the heaviest-traveled lines of the Moscow metro, the Arbat-Pokrovsky line, which bisects the center of the city. It’s very difficult and will take at least 24 to 48 hours to clear the debris and to reopen circulation. Moscow authorities have declared Wednesday a day of mourning for those who died in the accident. Russian President Vladimir Putin has expressed condolences to the families of those killed in the Metro train crash. Moscow Mayor Sergey Sobyanin said to the media that a criminal case should be launched into the accident. The Moscow Metro is carrying up to 9 million passenger trips each workday.