Some people openly protested against Russian President Vladimir Putin outside the funeral service for Kremlin critic and opposition politician Alexei Navalny, who died in a prison camp.

“Russia without Putin!” “Putin is a murderer!” “Russia will be free!” and “No to war!” people chanted people in chorus on Friday in Moscow. The atmosphere was tense, with a large contingent of uniformed Russian special police.

In a livestream on YouTube, Navalny’s team showed thousands of people chanting “Navalny, Navalny, Navalny” behind barriers made of metal bars. They chanted: “We do not forget. We do not forgive.”

After the funeral service in the church, the brown coffin was transported to Moscow’s Borisov cemetery for the burial, which was planned for 4 pm (1300 GMT). Thousands of people walked the half hour or so to the cemetery.

Putin’s spokesman Dmitry Peskov had previously warned against unauthorized protests.

Supporters and relatives of Navalny as well as human rights activists accuse Putin of having the leading Russian opposition figure murdered in custody. The Kremlin rejects this.