(Bloomberg) — Two Moscow subway workers were detained in theinvestigation into yesterday's train crash, which killed 22 peopleand injured 162, the deadliest incident in the city's undergroundsystem since 2010 suicide bombings.

The workers are suspected of violating safety regulations byimproperly installing the switch that failed when the train waschanging tracks, causing the three lead wagons to derail andtrailing cars to jack-knife, the Investigative Committee said in astatement on its website.

Nineteen people died on the scene and three more succumbed totheir injuries in the hospital, according to Emergencies Ministry.More than 100 people were still being treated by midday. Rescueworkers evacuated more than 1,200 people from the tunnel where thecrash occurred during morning rush hour, between the SlavyanskyBulvar and Park Pobedy stations in western Moscow. The train, onthe dark blue line that bisects the city, was heading away fromdowntown when it crashed.

The Russian capital's subway network, opened by Josef Stalin in1935, is the world's busiest outside of Asia, carrying as many as 9million people a day through 194 stations, according to the websiteof its operator, Moscow Metropolitan. The city government said lastyear it plans to spend $55 billion to upgrade and expand Moscow'sroad, rail and subway networks to boost use of public transport by45%.

'The End'

“I thought it was the end,” one passenger said in comments shownon Rossiya 24 television, describing how the lights suddenly wentout and smoke filled the carriages. Emergency workers removed someof the injured by helicopter to circumvent traffic jams.

Some of the relatives and friends of the injured who rushed tolocal hospitals said they were prevented by officials from learningthe status of people who were hurt.

“I was told they won't give him a phone and they won't let himspeak to me,” Natalya Sedykh, 23, said in televised remarks abouther boyfriend, Valery.

Moscow Mayor Sergei Sobyanin visited the scene as rescue workersmoved people to safety. Sobyanin, a former chief of staff toPresident Vladimir Putin, made improving transportation and rootingout corruption the focus of his administration after taking over in2010 from Yury Luzhkov, who had governed the city of 11.5 millionfor 18 years.

Russia's ranks behind Ghana, Montenegro and Albania at 93rd outof 148 nations for the quality of its infrastructure, according tothe World Economic Forum's latest Global CompetitivenessReport.

A fire broke out in a subway tunnel near the Kremlin last year,prompting the evacuation of about 4,500 people and snarlingdowntown traffic. In 1982, eight people died when an escalator inone of Moscow's subway stations collapsed.

Security was stepped up across the subway network after 40people were killed at two downtown stations in March 2010 by twofemale suicide bombers.

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