A large explosion in a stadium the Chechen capital, Grozny, has killed the Moscow-backed president of the rebellious Russian republic and at least 13 people other people.
Russian President Vladimir Putin confirmed the death of Akhmad Kadyrov, calling him a "heroic man."
The commander of Russian forces in Chechnya, General Valery Baranov, was also in the stadium when the blast occurred, but there were conflicting reports on whether he survived the attack.
Dozens were wounded in the blast that took place (at Dynamo Stadium) during Victory Day celebrations, marking World War Two defeat of Nazi Germany by the former Soviet Union.
Reports from the scene say the blast may have been caused by a landmine planted under the stands where the officials were seated.
There have been no claims of responsibility, but the Russian Defense Ministry immediately blamed Chechen separatists. The Itar-Tass news agency reported that five people were detained on suspicion of involvement.
Chechen rebels have carried attacks on Russian national holidays in the past. The rebels and Russian troops are locked in a guerrilla war that has claimed thousands of lives.
Today's (Sunday's) explosion came just two days after Russian President Vladimir Putin was sworn in for a second term in office.
Chechnya declared independence from Russia in the early 1990's. Russian troops fought a three-year war against rebel forces before withdrawing in 1996. They swept back into Chechnya in 1999.
Information for this report is provided by AP, AFP and Reuters.