The flooding in the Black Sea region killed 171 people—including 153 in the town of Krymsk and its suburbs—after torrential rain left behind nearly a foot (30 centimeters) of water.
The flash flood turned Krymsk's streets into swirling, muddy rivers and filled one-story homes nearly to their ceilings in the middle of the night on July 6-7. Many of those who died were elderly residents unable to escape in time.
Angry locals blamed local officials, saying they failed to warn residents of the coming disaster.
Russia's chief investigative body said in a statement Sunday that three local officials, including mayor of the town of Krymsk and the head of the Krymsk region, had received warnings about a possible flooding in the area but failed to organize the issuing of proper warnings and the evacuation of residents. The Investigative Committee also said the officials were being questioned as suspects regarding negligence that caused deaths.
Top Russian officials, including President Vladimir Putin, have insisted the fatalities were caused by an act of nature, but also have said the early warning system in Krymsk was inadequate.
More than two weeks after the deadly floods, Emergency Ministry officials and volunteers are still in the area, helping tens of thousands people left homeless or with few possessions.