Tripoli, Feb. 19 (Reuters): US warplanes carried out air strikes against Islamic State-linked militants in western Libya today, killing as many as 40 people in an operation targeting a suspect linked to two deadly attacks last year in neighbouring Tunisia.

It was the second US air strike in three months againstthe IS in Libya, where the hardline Islamist militants have exploited years of chaos following Muammar Gaddafi's 2011 overthrow.

The Pentagon said it had targeted an IS training camp and killed a Tunisian militant linked to major attacks on tourists in Tunisia.

The mayor of the Libyan city of Sabratha, Hussein al-Thwadi, said the planes struck at 3.30am, hitting a building in the city's Qasr Talil district, home to many foreigners.

He said 41 people had been killed and six wounded. Photos released by the municipal authorities showed a massive crater in grey earth. Several wounded men lay bandaged in hospital.