Muscovites observed a day of mourning on Wednesday as workers and investigators rummaged through the scene of a fatal metro derailment that claimed at least 23 lives and injured more than 160 others the day before.
Mourners paid their respects to the victims, laying flowers at the entrances of the Slavyansky Bulvar and Park Pobedy metro stations on the Dark Blue Line in western Moscow. Tuesday's crash — the deadliest technical accident in the metro's 79-year history — occurred during morning rush hour, when three metro cars traveling at 70 kilometers per hour skidded off the rails between the two stations.
See the photo gallery: Moscow Mourns Victims of Fatal Metro Crash
Soon after Moscow Mayor Sergei Sobyanin vowed that those responsible for the accident would be severely punished, Russia's Investigative Committee identified two rail technicians as suspects.
The technicians, Valery Bashkatov and Yury Gordov, had been responsible for overseeing work performed on railway switch mechanisms between the two stations.
In a statement published on its website on Wednesday, the Investigative Committee said it believed that the accident was caused by a faulty railway switch that had been fastened using improper wiring that could not withstand the normal passage of trains.
The suspects could face charges under Article 263 of the Russian Criminal Code on violations of rules for transportation safety. The law states that negligence entailing the deaths of two or more people is punishable by four to 10 years in prison.
The Investigative Committee also said that it was working on a chronology of events that led to the accident and that it was in the process of checking the licenses of contractors and subcontractors performing work on the city's metro system.
The conductor involved in the accident — whom authorities had declared dead before later retracting their statement — regained consciousness at a Moscow hospital on Wednesday, Interfax reported.
As more than 150 commuters remain in hospitals, Moscow's volunteer organizations have mobilized to support the victims, organizing three four-day blood clinics across the city.
A wave of international condolences has also come in after the accident. Residents of Kiev laid flowers and lit candles in front of the Russian Embassy, which just last month had been the scene of a disorderly protest linked to Russia's perceived role in the crisis in Ukraine.
The U.S. Embassy in Moscow, United Nations Secretary-General Ban Ki-moon, as well as Armenian President Serzh Sargsyan and Belarusian President Alexander Lukashenko, are among those who who offered their condolences to the victims' families and friends.
Train service remains interrupted on the Dark Blue Line between the Kievskaya and Molodyozhnaya stations. Deputy Mayor Pyotr Biryukov told reporters that service would be restored by Friday morning, Interfax reported.
Since January, 13 major technical issues have been recorded in the Moscow metro. Two of those incidents were deadly.