ISLAMABAD, Pakistan - Pakistani security forces taking part in fresh clashes near the Afghan border killed 10 suspected militants and wounded 25 others Sunday, a government official said.

More than 100 people, most of them militants, have been reported killed in the fighting in Bajur tribal region in the last five days. The region is a suspected hideout of al-Qaida leader Osama bin Laden and his No. 2, Ayman al-Zawahri, and it has been the focus of a major Pakistani military operation as well as ongoing U.S. concern.

Security forces used helicopter gunships, fighter jets and heavy artillery to attack suspected militant positions Sunday in the Loi Sam, Rashakai, Tang Khata and Gollokass areas of Bajur, said Iqbal Khattak, a senior government official.

"In the fresh operation that started this morning security forces killed 10 more militants, he said. "This figure can go higher as the fighting is going on."

The government said late last month that it would cease military operations in Bajur for the Muslim holy month of Ramadan, but it reserved the right to retaliate against insurgent activities. It was unclear Sunday if the offensive would continue through the rest of Ramadan.

Hundreds of militants were reported killed in Bajur in August due to the military offensive.

The latest clashes come amid tension between the U.S. and Pakistan over the Muslim nation's role and sovereignty in the war on terror.

U.S. officials are worried that Pakistan has not done enough to to flush out militants from the tribal areas, and that its intelligence agencies might even be secretly aiding insurgents. Al-Qaida and Taliban militants are believed to have found safe havens in the tribal areas from which to plan attacks on U.S. and NATO forces across the border in Afghanistan.

A series of suspected U.S. missile strikes and an American-led ground assault in Pakistani territory in recent days, however, have stirred anger and prompted Pakistan's government to lodge protests.

Although Pakistan has vowed to defend its territorial integrity and publicly denounced the U.S. incursions, top officials have indicated they would prefer resolving the conflict through diplomatic means.