The Kremlin-backed president of Chechnya (search)and more than 20 other people were killed Sunday when a bomb ripped through the VIP section at a stadium where Chechens were marking the defeat of the Nazis in World War II, officials said.

The blast, which regional emergency officials said apparently was caused by a land mine, collapsed the bleachers into a jagged pile of torn wooden planks, sending up brownver the bleachers and shots split the air amid the chaos.

Footage on Russia's NTV television showed men in uniform dragging a man resembling Chechen President Akhmad Kadyrov (search) covered in blood away from the broken seating area. His death was reported by the Chechen Interior Ministry and was later confirmed by the regional military command, the ITAR-Tass news agency said.

Chechen Prime Minister Sergei Abramov (search) will become the republic's acting president, the Kremlin said.

Nobody immediately claimed responsibility but suspicion fell on separatist rebels, who have been fighting Russian troops for much of the last decade.

Police and soldiers launched an extensive search after the blast and detained at least five people, news reports said.

"Justice will take the upper hand and retribution is inevitable," Russian President Vladimir Putin said at the conclusion of Moscow's Victory Day parade on Red Square, ITAR-Tass reported.

The blast in the heart of the provincial capital, where Russian troops are omnipresent, underlined the intense security problems even as the Kremlin says normalcy is being restored. Russian soldiers are reported killed in near-daily small attacks by rebels and by rebel-set explosions.

A spokesman for the Emergency Situations Ministry, Sergei Kozhemyaka, said a second land mine was found near the VIP seats.

The explosion also killed Hussein Isayev, head of Chechnya's State Council, the Interfax news agency reported, citing Putin's representative in the southern Russian district, Vladimir Yakovlev. Eli Isayev, the region's finance minister, also reportedly was killed.

A top Russian commander, Col.-Gen. Valery Baranov, initially was reported killed, but officials later said he was in critical condition. The city's emergency medical center said 24 people in all were killed and 46 wounded.

The victims included a photographer for the Reuters news agency. Adlan Khasanov, 33, worked for the agency in Chechnya as a photographer and television cameraman since the late 1990s.

Russia marks the Allied victory over the Nazis every May 9 with military parades and fireworks around the country.

Security was especially tight amid fears of terrorism after a series of bombings that have killed more than 300 people in and around Chechnya and in Moscow since December 2002. A bomb exploded during a Victory Day military parade in the Caspian Sea port of Kaspiisk two years ago, killing 43 people, including 12 children.

Grozny, the war-ruined Chechen capital, has a huge presence of Russian forces, but they have not been able to purge insurgents from the city. Sappers gingerly inspect the city's main thoroughfares for mines daily.

The latest fighting in Chechnya began in September 1999. Despite superior numbers and firepower, Russian troops have been unable to uproot the rebels from their mountainous hideouts or banish them entirely from Grozny.

Kadyrov was a rebel commander during the separatists' 1994-96 war that ended with Russian forces withdrawing. However, he became disenchanted during the period of Chechnya's de-facto independence, complaining of the growing influence of the Wahhabi sect of Islam in the republic.

He broke with Aslan Maskhadov, who had been elected Chechen president in 1997, and in 2000 the Kremlin appointed him the republic's top civilian administrator. He was elected president in an October vote widely criticized as fraudulent.

The election was portrayed by the Kremlin as a substantial step toward restoring order to Chechnya.

Refugees who have returned to Chechnya say Kadyrov's administration has withheld promised compensation for six months or more and many Chechens complain of seizures of civilians under his administration.

Kadyrov's son, Ramzan, runs a security force that is widely blamed for civilian disappearances. Putin met Sunday afternoon with the younger Kadyrov, the Kremlin press service said, although more information was not available.

Russian authorities have blamed Chechen rebels for most recent attacks, including a Feb. 6 suicide bombing on a Moscow subway that killed more than 40 people and wounded dozens.