A blast tore through a Victory Day parade in a southern Russian republic bordering rebel Chechnya today, killing at least 32 people, including 12 children.
President Vladimir Putin vowed to hunt down and punish the attackers, whom he described as "scum" who should be treated like Nazis.
He blamed the attack on "terrorists," the usual Kremlin term to describe separatist rebels in Chechnya, which neighbors the impoverished province of Dagestan where the attack took place.
"This crime was carried out by scum who hold nothing sacred," Mr Putin told a solemn Kremlin reception after a parade in Moscow's Red Square to mark the defeat of Nazi Germany 57 years ago.
"We have every right to treat them as Nazis, whose sole aim was to spread death, sow fear and to murder," he said. The audience observed a minute of silence.
Mr Putin says Russia is fighting the same brand of militants in Chechnya that Washington blames for the September 11th suicide attacks on the United States.
Police said a remote-controlled mine hidden in bushes exploded as a military band surrounded by children and World War Two veterans marched through Kaspiisk, a Caspian Sea port some 1,000 miles from Moscow.
"Our latest information is that 32 people died, including 12 children," Mr Abdul Musayev, head of the interior ministry press office in Mahkachkala, told reporters.
He said nuts, bolts and nails in the device were designed to cause maximum injury. Some 130 people were injured in total.
Security services meanwhile sealed off the area as sappers checked the area for more mines.
In Moscow, police said they were beefing up security in the capital following the attack, the bloodiest since apartment bombings in September, 1999, killed more than 300 people.
Television pictures showed military caps, boots, wrecked drums and other musical instruments scattered across Kaspiisk's blood-splattered main street.
Wounded servicemen covered in blood, their uniforms torn in the explosion, were seen on stretchers receiving treatment in hospital, while nurses tried to resuscitate one victim.
NTV correspondent Mr Ruslan Gusarev said the blast erupted as the band was on foot, not in a bus as initial reports suggested, and surrounded by crowds of children and World War Two veterans.
"The scene is horrifying. There are body parts everywhere and an overpowering smell of blood," he told the private television station by telephone.
The attack came just before Mr Putin addressed the traditional Victory Day parade outside the towering red walls of the Kremlin, urging the nation to unite to defeat the common threat as it had done to crush Adolf Hitler.
"Only by uniting the effort of the people and the state can we confront these threats," Mr Putin said.