MOSCOW — Russia’s most prominent talk-radio station, Echo of Moscow, came under attack on Monday when a knife-wielding man broke into the studio and stabbed an announcer in the throat, renewing worries about the safety of journalists here.

The attack splattered blood around the station’s green room, where guests wait to take part in programs. The announcer who was stabbed, Tatyana Felgenhauer, is also the station’s deputy editor and was not on air during the attack, after which security guards tackled and detained the man.

Echo of Moscow is among the dwindling number of news media outlets in Russia that report on a range of political views, including those critical of the government. That has put the station in a crucible of political pressure. Its journalists often receive death threats, and the broadcaster’s editor, Aleksei Venediktov, once opened his apartment door to find a grim warning — a block of wood with an ax lodged in it.

The station’s green room is decorated with a cardboard cutout of Mr. Venediktov, and has been a much-frequented spot for dozens of liberal commentators and politicians in the capital.