Thousands of mourners attended the funeral of Kadyrov, 52, who was once a leading Chechen separatist but later backed the Kremlin. Russian officials told Reuters that the security situation at the funeral in his home village of Tsentoroi, some 30 miles from the capital Grozny, was under control.
The explosion Sunday ripped through a stadium grandstand in Grozny during a Victory Day parade celebrating the anniversary of the Nazi defeat in World War II.
There was no claim of responsibility for the blast, but suspicion inevitably fell on Chechnya's pro-independence rebels, who are fighting both Russian soldiers and Chechen police and security forces employed by the regional government and Kadyrov's administration.
Rebel leader Aslan Maskhadov, in an interview with the rebel news agency Chechenpress, denied any involvement.
Russian news agencies quoted investigators as saying they were trying to determine how a bomb could have been planted in such a tight security area.
Previous major attacks in Chechnya have been followed by massive efforts to uncover the perpetrators, with troops and security forces carrying out intrusive searches and detaining scores of people.
Kadyrov's younger son Ramzan runs the region's security service, which has been accused of being behind civilian disappearances and killings. Both Kadyrovs have denied the accusations.
Chechen Prime Minister Sergei Abramov took over as acting president and Russian news agencies reported Monday that he appointed Ramzan Kadyrov as first deputy chairman of the government. News reports said officials promised a new presidential election in the region within four months.
Despite confident talk from Russian officials, the outlook appeared bleak for Putin's plans to establish an effective authority in Chechnya that would eventually snuff out the separatist rebellion.
"This will lead to quite serious changes in the system of rule in the republic, because the system that was formed was built in accordance with (Kadyrov's) methods of controlling the situation," Shamil Beno, a former separatist Chechen official who is now a human rights activist in Moscow, said on Echo of Moscow radio.
The Kremlin appointed Kadyrov as Chechnya's administrator in 2000. He was elected president in October after most of his key competitors dropped out of the race, leading many regional observers and the press to question the election's legitimacy.
Successful efforts on the part of Kadyrov and the Kremlin to get rid of his power rivals have left few potential successors of quality for Putin to choose.
For the past four years his main political rivals had been kept out of Chechnya, losing touch with voters and their power base in the region.
Among the others killed in Sunday's blast were Khusein Isayev, the head of Chechnya's State Council, and Reuters photographer Adlan Khasanov. The explosion also wounded top Russian military commander in Chechnya, Col.-Gen. Valery Baranov, who was in critical condition and had a leg amputated.
In total, six people were killed and that 57 people were wounded in the bombing, Chechen Deputy Minister of Emergency Situations Akhmed Dzheirkhanov said Sunday. He did not confirm Russian media reports of a seventh death overnight, according to the Associated Press.