Iraqi forces backed by tribesmen launched attacks on militant groups in Iraq's western province of Anbar, killing 57 militants, the Defense Ministry said on Monday.

The battles overnight and on Monday morning also destroyed two heavy machine guns fixed on two vehicles, the ministry said in a statement emailed to Xinhua.

A provincial police source and witnesses told Xinhua that the government troops intensified shelling on the cities of Ramadi and the nearby city of Fallujah since late Sunday and early Monday, killing and wounding unknown number of people.

Anbar province has been witnessing fierce clashes that flared up after Iraqi police dismantled an anti-government protest site outside Ramadi last December.