(CNN)An LGBTQ rights activist who was murdered in St. Petersburg had received death threats and was named on a website urging vigilante violence, campaigners have said.
Yelena Grigoryeva was confirmed dead by friends and fellow activists, who paid tribute to her on Tuesday.
Russia's Investigative Committee, a state body that handles major crimes, reported that a woman born in 1979 was found dead in with multiple knife wounds on Sunday evening.
Grigoryeva was a prominent campaigner on many issues, including LGBTQ rights and freedom for political prisoners.
Homosexuality was decriminalized in Russia in 1993, but homophobia and discrimination are still common.
Grigoryeva also protested against Russia's backing of the conflict in eastern Ukraine and its annexation of Crimea, Olga Smirnova, a friend and fellow activist, told CNN.
Campaigners told CNN that Grigoryeva had received numerous death threats.
A spokeswoman for the Russian LGBT Network told CNN that Grigoryeva's name was included on a Russian website that identified LGBT activists and called for vigilante action against them.
"We don't know who is behind the project, but they collected personal information about LGBT activists like their names, photos and addresses, and published it online, and they called for people to hunt or to kill them," the spokeswoman told CNN.
"The situation is scary, especially for LGBT activists. People feel targeted and they feel that the police are not going to help," she added.
Asked about threats that Grigoryeva received, Smirnova said: "She did not just complain, she kept us informed about all the threats that she received. They were of different kinds — there were threats related to her political position and there were threats specifically on the LGBT line."
Smirnova told CNN that not all the threats against Grigoryeva were anonymous, but declined to speculate on the likely perpetrator.
"This is undoubtedly a premeditated hate crime," she said. "But I cannot say with certainty that, for example, this is only over an LGBT agenda or whether a political agenda which was the motive."
Laurie Bristow, the British ambassador in Moscow, said in a statement on Twitter that he was "shocked and saddened at reports of the murder of human rights activist Yelena Grigoryeva."
In a statement published online, Russia's Investigative Committee said that an investigation was underway.