A teenage Russian street musician who has spent nearly a month in jail after singing anti-Kremlin songs was handed more jail time on Tuesday in a case rights activists say shows how stifling wartime censorship has become.

Diana Loginova, 18, who sings in a group called Stoptime, was arrested in her native St. Petersburg last month after giving a series of impromptu street concerts in the heart of Russia's second city in which she belted out cover versions of songs penned by Kremlin critics with sometimes subtle anti-war and, in one case, anti-Putin lyrics.

Loginova, whose performances prompted young passersby to sing along and saw the band swiftly build a social media audience of over 50,000 followers, has already been jailed twice after video of the concerts went viral online and attracted the attention of the authorities.