The New York-based Committee to Protect Journalists (CPJ) is urging Russian authorities to conduct a “thorough, unbiased, and effective” investigation into the killing of the chief editor of a newspaper in the Siberian city of Minusinsk, and bring those responsible to justice.

"Russia is a country where too many journalists have been murdered for their work while their killers walk free," CPJ Europe and Central Asia Program Coordinator Nina Ognianova said in a May 25 statement. "This toxic cycle of impunity must be reversed once and for all."

Russian investigators said Dmitry Popkov's body was found with multiple gunshot wounds in Minusinsk late on May 24.

They said they have opened a murder investigation and are looking into several possible motives including a link to the victim's "professional activities."

Popkov, 42, was the chief editor of Ton-M newspaper.

He is the second journalist to be killed in Russia this year, according to the CPJ.

The media watchdog said Popkov was known for his "investigative reports on abuse of power and corruption, as well as his criticism of functionaries" from the ruling United Russia party.