MOSCOW — Russian police have detained a new suspect in the fatal stabbing of an LGBTQ activist near her home in St Petersburg after last week taking the wrong man into custody, investigators said on Thursday.

Elena Grigoryeva, 41, was stabbed eight times in the face and back the night of July 20 by a local resident she had been drinking with, following an argument between the two, the Investigative Committee said in a statement.

The agency, which handles major crimes, last week arrested a man born in Soviet Kyrgyzstan who had known Grigoryeva, but said he had accused another man of the murder during questioning and that further investigation had shown his allegations to be correct.

Grigoryeva campaigned for gay rights and also took part in anti-war protests and rallies on other issues.

Grigoryeva was murdered last month after finding her name listed on a website inspired by the horror movie "Saw" that offered prizes for people to "hunt" gays.

According to friends' and colleagues' online posts, Grigoryeva was worried about her safety after she found her name and personal information listed on the snuff site.

“I learned today that Lena asked a mutual friend to take care of her cat in the event of her death when she was threatened with murder,” friend and fellow activist Dinar Idrisov wrote on Facebook.

“The state of Russia was obliged to guarantee her the right to life,” Idrisov wrote. “Lena and her lawyer appealed to law enforcement agencies both on the fact of violence and on the fact of threats, but there was no noticeable reaction.”

Days before she was murdered, Grigoryeva was posting on social media in an attempt to get the website taken down.

“Law enforcement agencies have still not done anything to find the creators of this ‘game’ and bring them to justice,” Grigoryeva wrote on Facebook on July 18. She called on those opposed to the website to contact the Russian prosecutor’s office and the FSB, Russia’s intelligence agency.

“IMPORTANT!” Grigoryeva wrote. “The Russian LGBT network has repeatedly tried to find people affected by the actions of this group, but failed. We did not find a single attack case directly related to this group.”

Three days after her post, Grigoryeva was dead.

A spokesman for the Council of Europe has urged Russia to conduct a full and transparent investigation into the murder, noting on social media what it said were rising hate crimes in Europe and the need to protect LGBTQ communities.

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