Police have detained a man who has confessed to killing two women in a central Russian city, and then trying to mislead investigations by scrawling a message at the crime scene demanding freedom for jailed members of the Pussy Riot band.

The suspect — university professor Igor Danilevsky — was detained Thursday in Kazan, Russia's Investigative Committee said on Friday. It said Danilevsky wrote "Free Pussy Riot" on a wall in the victims' blood because he wanted the deaths of the woman, 38, he dated and her mother, 76, to appear as if they were a "ritual killing."

The committee said Danilevsky, 38, had persuaded the woman to take out a loan to repay his debts, and promised to marry her. Police had found the knife used to stab the women to death and disfigure their faces and bodies, it said.

Three members of the band were sentenced to two years in prison earlier this month for a February "punk prayer" in Moscow's main cathedral entreating the Virgin Mary to save Russia from Vladimir Putin, who at the time was on the verge of winning a third term as Russian president. The trial, widely seen as Kremlin-orchestrated, caused an international furor, with celebrities such as Paul McCartney urging Russian authorities to free the band.

The jailed band members' attorney had called the two women's murder "either a horrendous provocation or a psychopathic" case.

Kremlin-friendly media and Orthodox Church clerics had seized upon the alleged link between the murder and the band to lambast the artists and their supporters, and compared them to mass murderer Charles Manson, whose followers used the blood of victims to write on the walls of their houses.

Some Russian publications ran headlines claiming Pussy Riot supporters "committed" or "inspired" the double homicide. The coverage was full of the mostly negative terms used by Kremlin-friendly television networks and media in their coverage of the protesters' trial.

The Orthodox Church has called the band's stunt sacrilegious, but hundreds of artists, musicians and other intellectuals have signed petitions urging authorities to free them.