A hand grenade exploded on Monday outside the studios of an anti-government Georgian television station involved in an opposition street campaign to oust President Mikheil Saakashvili, the station said.

Maestro Television, which broadcasts mainly to the capital Tbilisi, said no one was hurt in the blast. The door to the studios was sprayed with shrapnel.

"There was an explosion just in front of our door but no one was injured," said Maestro producer Natia Mikiashvili.

Tensions in the former Soviet republic are running high, after six weeks of opposition protests and roadblocks in Tbilisi demanding Saakashvili resign over his record on democracy and last year's disastrous war with Russia.

Police and protesters clashed briefly in early May, and New York-based Human Rights Watch said last week it had documented a pattern of late-night attacks on protesters that "appeared to be a concerted effort to intimidate the demonstrators".

Analysts and diplomats say the opposition probably lacks the numbers to unseat Saakashvili, but the longer the stalemate drags on the greater the risk of violence.

Reuters