Thousands of mourners gathered in Moscow on Friday outside the funeral for Alexei Navalny, the 47-year-old outspoken critic of Russian President Vladimir Putin who Kremlin officials say was found dead in a remote arctic prison last month.

What happened at the funeral?

Chanting “We are not afraid!” Navalny’s supporters lined up behind barriers in front of the Mother of God Quench My Sorrows church in Moscow as his casket was whisked in for a brief ceremony before being taken to the nearby Borisovsky Cemetery, where he was buried.

Navalny’s body was lowered into the ground as Frank Sinatra’s “My Way” was played in the background, according to reporters who were there.

The public was barred from entering the church or cemetery by police, who prevented people from leaving flowers or taking pictures. Foreign diplomats, including U.S. ambassador to Russia Lynne Tracy, were photographed holding roses outside the church.

Navalny’s parents, Lyudmila and Anatoly, attended the funeral. But other members of the family, including Yulia Navalnaya, Navalny’s widow who has vowed to take up her late husband’s fight, live outside Russia for their safety and were not seen at the church on Friday.

Who was Alexei Navalny?

Navalny was born on June 4, 1976, near Moscow.

A former lawyer, he rose to prominence in the early 2000s and 2010s for leading nationalist marches and exposing what he called corruption among the Russian elite, describing Kremlin leaders as “crooks and thieves.”

Navalny used drones to expose some of the lavish lifestyles of senior Kremlin officials, posting images of mansions and yachts used by ex-Russian President Dmitry Medvedev and a palace built on the Black Sea for Putin’s personal use.

Navalny survived an assassination attempt with a nerve agent in 2020 and had been imprisoned since returning to Russia in 2021. He was being held in a Russian jail about 40 miles north of the Arctic Circle.

On Feb. 16, Russia’s Federal Penitentiary Service said in a statement that Navalny lost consciousness and died after taking a walk and could not be resuscitated.

Kremlin officials say Navalny died of “natural causes.” His family and his supporters have described his death as “murder.”

What was the U.S. reaction to his death?

Last week, the White House unveiled what it described as “major sanctions” against Russia in response to Navalny’s death and its ongoing war in Ukraine.

President Biden, who met privately with Navalnaya in San Francisco, praised Navalny for his bravery — and put the blame for his death squarely on Putin.

“Make no mistake,” Biden said. “Putin is responsible.”