TIKRIT, Iraq, June 29 (Reuters) - A bomb blast in northern Iraq's Salahuddin province killed five policemen and wounded two when it struck their patrol on Sunday, police said.

The explosion in the town of Dhuluiya, 70 km (45 miles) north of Baghdad, was the latest in a series of attacks by militants on Iraqi forces trying gradually to take over responsibility for Iraq's security from the U.S. military.

Police gave conflicting accounts of the cause.

Colonel Fadhil al-Jubouri, who heads a joint U.S. and Iraqi security centre in the Salahuddin provincial capital Tikrit, said the blast was caused by a roadside bomb.

Other police sources said a suicide car bomber drove into the patrol. All gave the same casualty figures. (Reporting by Sabah al-Bazee, writing by Tim Cocks; editing by Andrew Dobbie) (tim.cocks@thomsonreuters.com; Reuters Messaging: tim.cocks.reuters.com@reuters.net))

AlertNet news is provided by