One of the many flooded homes in the southern Russian city of Krymsk on Sunday. Electrical power is still out in the town.
MOSCOW — President Vladimir V. Putin declared a national day of mourning and promised financial compensation for the victims of flash floods in southern Russia on Sunday, as emergency officials said the number of people killed had risen to more than 150.
Mr. Putin toured the deluged region by air on Saturday evening, flying over towns that were inundated by rivers of muddy water churning through the streets, submerging cars and ravaging buildings. “Like a tsunami,” Mr. Putin said.
Questions about whether official negligence or misconduct had played a role in the disaster quickly came to the fore. The federal Investigative Committee said it had opened a criminal inquiry and would examine the authorities responsible for emergency preparedness to determine if more should or could have been done to prevent the deaths.
But officials were quick to rule out the possibility that the flooding in the hardest-hit town, Krymsk, had been made worse by water released from a local reservoir.
The federal emergency situations minister, Vladimir Puchkov, reported that he personally flew over the Neberdzhayevskoye reservoir in an Mi-8 helicopter and saw no breaches. The Investigative Committee said it found no problem with the reservoir, where small amounts of water are routinely released.
“The normal mode of the dam did not affect the development of the tragic events,” the committee reported, adding that there had been “no mass emissions or water overflows.”
About 11 inches of rain fell Friday night and early Saturday on the Krasnodar region near the Black Sea, the most punishing rains there in recent memory. The heaviest downfalls were reported between 1 a.m. and 3 a.m. Saturday, and they were quickly funneled into torrents by the hilly terrain. Thousands of homes were flooded, in many cases as their occupants slept.
Emergency officials reported that more than 2,700 people were evacuated, and dozens were hospitalized.
More rain fell in Krymsk on Sunday. Electric power was still out, but railroad service was restored to the region. Hundreds of soldiers were sent to the area to assist in cleanup operations.
Most of the deaths from the floods were in Krymsk, but there were also fatalities in Gelendzhik, a resort town on the Black Sea about 140 miles from Sochi, where the 2014 Winter Olympics will be held.
Officials said that so much rain fell so quickly that there was little chance to warn people on a wide scale.
“The kick of the elements was so powerful and treacherous that it left people little chance of survival,” Dmitri O. Rogozin, the deputy prime minister, wrote on Twitter.
Mr. Rogozin said that the authorities were concerned about the spread of disease in the wake of the floods, and that they were providing free vaccinations against Hepatitis A and other ailments.
The authorities were also working to distribute clean drinking water, and they had set up emergency stations to help people replace lost identification documents, including passports, so that they could obtain government assistance.
Mr. Putin, who returned to the presidency in May after four years as prime minister, seemed intent on demonstrating a forceful response to the first big natural disaster in Russia since his inauguration.
He promised that each family affected by the flooding would immediately receive about $300 for emergency necessities, followed by about $4,600 per person for lost property. Families that suffered a fatality would receive compensation up to about $60,000, according to Mr. Putin’s Web site.
Mr. Putin said that Monday would be a national day of mourning for the flood victims and for 14 Russians who died Saturday in a bus crash in Ukraine. The victims of the crash were making a religious pilgrimage to a monastery.
