U.S. B-52 warplanes bombed the Iraqi front line between the town of Dohuk and the city of Mosul in the north of the country on Wednesday. U.S. warplanes have been targeting Mosul and the northern oil hub of Kirkuk in recent days as Washington slowly moves troops into the region to open a new front in its ground war on Iraq , which has been waged mainly from the south via Kuwait.

This correspondent saw the Americans make at least three sorties, dropping about half a dozen bombs each time. Plumes of smoke billowed above the horizon in the direction of Mosul.

More B-52s passed overhead during the late morning.

"There has been very heavy bombing here today," Kurdish tribal leader Farhan Sharafani told Reuters by satellite telephone from a location northeast of Mosul.

Sharafani also said Kurdish "peshmerga" fighters had seized some territory overnight, including a bridge and two villages near the town of Bardarash, which is northeast of Mosul.

He said they captured 40 Iraqi soldiers and two officers. Two peshmerga fighters were killed in the clash, he added.

TURKISH TRUCKS

In a separate development, this correspondent saw a convoy of about 25 Turkish-registered trucks heading south along the road toward Dohuk on Wednesday morning with a U.S. military escort.

The Iraq-Turkey border has been closed since before the United States and Britain launched their war to topple President Saddam Hussein on March 20.

A U.S. soldier accompanying the convoy declined to say what the trucks were carrying or where they were headed.

The United States has deployed a small number of troops in northern Iraq to operate alongside the Kurdish fighters opposed to Saddam's rule.

Last month, in a big setback for Washington, Ankara's parliament denied permission for up to 62,000 U.S. invasion troops to use Turkish territory to open a northern front against Iraq.

Ankara has reserved the right to bolster its own small military presence in northern Iraq if it sees a danger of the Kurds establishing an independent state that, it believes, would rekindle armed Kurdish separatism in Turkey's southeast.

Secretary of State Colin Powell was visiting Ankara on Wednesday to seek Turkey's agreement not to send a large force into Iraq for fear it could undermine the U.S.-led war.

PHOTO CAPTION

An American B-52 takes off from the U.S. air base at RAF Fairford, England, Monday, March 31 2003. The base is being used by a fleet of the heavyweight bombers that continue their missions in Iraq . (AP Photo/Dave Caulkin)