The criminal case against Russian journalist Ivan Golunov, who said police planted drugs on him and beat him, has been dismissed following an international outcry.
The rare reversal of a criminal prosecution suggests the Kremlin is nervous over social dissent in recent months.
After fingerprint and DNA analysis, “the decision has been made to stop the criminal case against citizen Golunov and remove the charges against him because of the lack of proof of his involvement in the crime committed,” interior minister Vladimir Kolokoltsev said in a video statement.
The reporter for the Latvia-based Russian news site Meduza would be released from house arrest on Tuesday, he added.
Mr Kolokoltsev also said he would ask Vladimir Putin, the Russian president, for permission to fire the head of the Moscow police's anti-narcotics department and the police chief of the western Moscow district. The officers who arrested him have been suspended while the investigative committee examines their actions.
Golunov, who is known for his investigations of high-level corruption in the Moscow city government, was arrested on Thursday and charged with selling designer drug mephedrone and cocaine. He was later taken to the hospital after complaining police had punched him and stood on his chest.
The evidence appeared flimsy from the start, with police soon admitting that other people's DNA was present on the drugs seized and that alleged photographs of paraphernalia in Golunov's home were actually taken at another location in the Moscow region.
Meduza said Golunov had recently filed a draft of another hard-hitting expose and had regularly been receiving threats related to his work.
Muscovites have been picketing the police headquarters, and three major Russian newspapers ran front pages on Monday declaring that “I/we are Ivan Golunov,” and a protest was planned for Wednesday.
Amnesty International said his arrest was part of an alarming trend of authorities “planting drugs on their targets to shut them up with a jail sentence”.
The editors of Meduza and the independent publications Novaya Gazeta and The Bell said in a statement on Tuesday that Golunov's release was the result of an “unprecedented campaign of journalist and civic solidarity”.
“Together we did something incredible: stopped the criminal persecution of an innocent person,” they said.
A group of journalists including Golunov would investigate the still unnamed officers behind his arrest, they added.
The ending of Golunov's case comes a day after Oyub Titiyev, a human rights activist who also said police planted drugs on him, was released from prison on parole in Russia's Chechnya republic.
Government-backed projects have sparked local protests in several Russian cities after Mr Putin's approval ratings slipped with an unpopular hike in the pension age last year.
Protests in Yekaterinburg forced authorities last month to cancel the construction of a church in a downtown park.