Riot police have clashed with hundreds of mainly Tunisian immigrants during a protest against conditions at a detention centre on the tiny Italian island of Lampedusa.

Television footage showed riot police wielding clubs and beating the migrants as they jumped from a balcony near the island's commercial port.

The clashes came a day after migrants set their overcrowded holding centre on fire to protest Italy's policy of forced repatriations.

About 26,000 Tunisians and 28,000 people of other nationalities from Libya have arrived in Lampedusa this year since the beginning of the Arab uprising.

Three officers and a dozen protesters were hurt, Italian news agency ANSA said.

The clashes began after a peaceful protest by about 300 Tunisians turned violent. The Tunisians were marching through the port of Lampedusa carrying banners and chanting "Liberty, liberty".

They stopped at a small gas station, where they were surrounded by police in anti-riot gear. ANSA reported that police tried to block protesters from lighting fire to the gas tanks.

Explosion threat

Al Jazeera's Karl Stagno Navarra, reporting from nearby Malta, said: "There was a riot within the compound which hosted some 1,500 Tunisian migrants that landed in the island over the past four days.

"They are objecting to being deported back to Tunisia as per the agreement between Italy and Tunisia.

"Our understanding is that most of these migrants have escaped the camp and are roaming the island, and they are clashing with police and the locals.

"There is a standoff also next to the petrol station where some migrants have threatened to blow up the place up if the police decide to move in."

Angry Lampedusa residents surrounded the town hall, calling on Mayor Bernardino De Rubeis to take a stronger line against the migrants.

"I have to defend myself and am ready to use it," De Rubeis said, showing journalists a baseball bat stashed in the desk drawer in his office.

"It's like a war zone," he added, calling on the state to "immediately send helicopters and ships to evacuate the Tunisians".

The UN refugee agency and several charities expressed their disappointment in the Italian government's handling of the situation.