MOSCOW (AP) — Russian news agencies say the head of Moscow’s subway system has been fired in the wake of a rush-hour derailment that killed 22 people and injured 136 others.

Moscow mayor Sergei Sobyanin on Tuesday dismissed Ivan Besedin, who has served in the post since 2011. Sobyanin said that the crash “has crossed out the major work that was carried out over the last years.” He was replaced with Dmitry Pegov, a former railway official.

One day after the deadly July 15 crash, investigators detained two Moscow subway workers and said they were preparing to file criminal charges against them.

In recent months, subway workers have complained of declining safety standards in the system and disorganized measures for aiding stricken passengers.

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