A crash that left at least 19 people dead after three cars derailed Tuesday on the Moscow metro was not the result of a terrorist attack, municipal authorities have said.
Deputy Mayor Pyotr Biryukov told journalists several hours after the incident on Tuesday morning that terrorism had been completely ruled out as the cause of the derailment, the Interfax news agency reported.
Preliminary reports seem to suggest that the cars derailed after a sudden decrease in electricity in the tracks connecting the western Slavyanksy Bulvar and Park Pobedy metro stations on the Blue Line.
The power failure triggered an alarm system in the tunnel, leading the train's driver to sharply slam on the breaks, a spokesman for the Emergency Situations Ministry told Interfax.
The agency cited an unidentified source close to the rescue operation as saying the the accident could also have been caused by a faulty fixture on one of the cars.
"The accident is likely to have been caused by mechanical damage to a fitting [that connected] the wheel frame with the body of the car," he was quoted as saying.
After separating from the tracks, one of the three cars smashed into the tunnel walls, deforming the carriage and leaving passengers trapped inside.
A statement posted on the Investigative Committee website said that investigators in Moscow had opened a criminal case into the accident on charges of violating transportation security.