Yury Budanov was jailed for 10 years in 2003 for the murder in 2000 of 18-year-old Elza Kungaeva.
His early release in January 2009 prompted protests by rights groups and officials in Chechnya.
Budanov was shot dead on June 10 on Moscow's Komsomol Avenue. Police arrested Magomed Suleimanov, from Russia's Chechen Republic, as a suspect in the murder in August.
Local citizens told RFE/RL that the leader of Russia's Liberal Democratic Party (LDPR), Vladimir Zhirinovsky, attended the ceremony last week for the unveiling of the memorial in Moscow.
The LDPR press service told RFE/RL that Zhirinovsky visited the site on November 24 but said the media should contact Valery Budanov -- Budanov's son, who joined the LDPR earlier this year -- for any comment.
Unveiled On Budanov's Birthday
Budanov told RFE/RL that the memorial stone was unveiled on November 24 -- his late father's birthday.
"I have initiated the placing of the memorial stone on that spot and people who respect my father sponsored the project," he said. "Our party did not cover any expenses. The idea to place the stone had been discussed with local citizens. They did not mind. The stone does not block any traffic or path."
He added that Zhirinovsky and 10-15 activists of the LDPR came to unveil the memorial stone.
A woman whose apartment windows face the newly unveiled memorial, told RFE/RL that "our yards and playgrounds cannot be turned into graveyards."
"A woman was killed nearby recently, will they place another stone here now?" the woman asked.
Officials in the Khamovniki district administration told RFE/RL that they are unaware of the stone.
It is generally very difficult to obtain permission to place a memorial or plaque in public places in Moscow.
Numerous agreements and bureaucratic proceedings must be arranged before such a memorial is approved by local authorities. The placing of a memorial without official permission is usually punished with large fines.
But Budanov's memorial neither received permission to be placed nor has anyone thus far been fined for erecting it.
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