A Moscow court overturned on Thursday an earlier court ruling that found a photo correspondent covering an unsanctioned protest guilty of taking part in it.

RIA Novosti photo correspondent Andrei Stenin was briefly arrested and then fined for taking part in an anti-government rally in front of the presidential administration in December. He denied the charge, saying he was covering the event.

The incident triggered a wave of police criticism among media outlets and rights groups.

The presiding judge said the earlier ruling was overturned after police officers who arrested the journalist provided new testimony.

"A check has shown that Stenin did not take part in the picket and was arrested by mistake," the judge said.

Police officer Vladimir Syakin said in the courtroom earlier on Thursday that Stenin was arrested by mistake as "he resembled a protester involved in the picket."

The state-run RIA Novosti agency issued a statement after the initial court decision to fine the correspondent, calling it "unjust" and confirming the journalist had been assigned to cover the event.

Chief editors of major media outlets, alarmed that the incident could have set a precedent for prosecuting journalists "performing their professional duty," published an open letter to the interior minister demanding protection for journalists.

Russia has been rocked by a series of police scandals recently, prompting President Dmitry Medvedev in December to order reform of the Interior Ministry, trimming police numbers and raising salaries in an effort to reduce corruption and attract a better class of applicants.

MOSCOW, February 4 (RIA Novosti)