The Kremlin has condemned an attack against Russian opposition politician Mikhail Kasyanov and said there was no reason to associate the incident with Chechnya's leadership.
Kremlin spokesman Dmitry Peskov made the comments on February 10 after the attack at a Moscow restaurant where Kasyanov was dining the previous night.
Video footage of the incident posted by the Kremlin-loyal website Lifenews shows two men approaching Kasyanov at his table, one of whom violently slams a cake into his face while the other appears to film the attack.
At least one of the men is then heard berating Kasyanov for his politics, calling him an "American agent." The footage appears to show another man linked to the assailants.
Three Chechen police officers were reportedly detained in Moscow in connection with the incident and an administrative case has been opened against them.
Kasyanov, a former prime minister under President Vladimir Putin and now a Kremlin critic, said he believes the attack was tied to his request that federal authorities investigate an Instagram post by the head of Chechnya, Ramzan Kadyrov.
Last week's post featured video footage of Kasyanov and a fellow opposition activist framed through what appear to be a sniper's crosshairs.
"I link this attack to my political activity," the Russian business daily RBC quoted Kasyanov as saying.
"I believe that today's attack is directly linked to Kadyrov's threats posted against me and because I filed a complaint against him with the Investigative Committee and the FSB [Federal Security Service]," he added.
Peskov told a teleconference with journalists that the incident "should not be associated with the leadership of Chechnya or any other Russian region."
"What we are talking about is an act of hooliganism, which, of course, must be condemned," he said.
Following the cake incident, Kadyrov mocked Kasyanov in a February 10 post on his Instagram account, posting a photograph of Russian pop star Nikolai Baskov smiling with cake on his face at a banquet together with the Chechen strongman.
"After Nikolai Baskov had cake thrown in his face, he is still complaining, running to all international authorities and asking for a repeat of the banquet," Kadyrov wrote.
Kadyrov and his allies this year have unleashed a torrent of hostile rhetoric, both on social media and in news outlets that are loyal to the state, against liberal politicians, activists, and journalists.
In addition to Kasyanov, those targeted have included Aleksei Veneditkov, editor in chief of the independent-minded radio station Ekho Moskvy, veteran human rights crusader Lev Ponomaryov, and opposition activist Ilya Yashin.
One such Instagram video was posted by Adam Delimkhanov, a Kadyrov ally and member of Russia's parliament from Chechnya. It showed Delimkhanov and other men chanting "Kadyrov is the rock of Russia -- Allah Akhbar!" on a Moscow bridge near the one where Russian opposition leader Boris Nemtsov was shot dead in February.
Many of Kadyrov's critics suspect he was behind Nemtsov's slaying. He denies involvement, and efforts by relatives and associates of Nemtsov to have him questioned have been thwarted.
Russian investigators said last month that five detained suspects from Chechnya had been charged with "committing the contract killing" of Nemtsov as he was walking near the Kremlin on February 27, 2015.
The man Russian authorities have identified as the suspected mastermind of the killing, a member of Kadyrov's security forces named Ruslan Mukhudinov, remains at large. Many former associates of Nemtsov believe the decision to kill him was made at much higher level than Mukhudinov.