A weekend firefight with suspected Taliban (searchguerrillas in eastern Afghanistan left two American soldiers dead, while hundreds of Taliban headed into the mountains to join a weeklong battle with U.S. and Afghan troops.

The two U.S. soldiers died and another was wounded in a 90-minute gunbattle Sunday in eastern Paktika province (search), near the Pakistani border. Four guerrillas also were killed.

It was the latest in escalating violence in Afghanistan, where guerrillas from the former Taliban regime have appeared to regroup, launching bolder and better coordinated attacks against Afghan government targets. Four U.S. soldiers have been killed during fighting in less than two weeks.

In the south, U.S jets and helicopters pummeled rebel positions for a seventh day in the mountains of Zabul province (search). U.S. troops and their Afghan allies have been battling for a week with Taliban forces.

Dozens of suspected Taliban have been killed in the onslaught, one of the fiercest since the hardline group was driven from power in late 2001.

U.S. warplanes bombed the area in Dai Chupan district for three hours before dawn on Sunday, then carried out several more bombing sorties before noon. Afghan soldiers sweeping the area after dawn saw 14 newly killed Taliban fighters, said Khalil Hotak, the intelligence chief of southern Zabul province.

There were no reports of casualties among government forces. Hotak's reports could not be independently confirmed. He spoke to The Associated Press at an operations center in Qalat, the provincial capital about 40 miles south of the fighting.

U.S. military spokesman Col. Rodney Davis said Saturday that 33 Taliban have been killed in the southern recent fighting, but Afghan officials put the insurgent death toll much higher.

The Dai Chupan district, an area of rugged mountain gorges and ridges, is believed to be Taliban stronghold from where they launch operations in neighboring provinces.

An Afghan military commander speaking from Larzab, one of the frontline locations in the battle, said Sunday that intelligence indicated more Taliban reinforcement fighters had arrived in the area.

"We have information that more than 250 Taliban entered Dai Chupan district from the neighboring district of Mizan," said Gen. Haji Saifullah Khan, speaking with AP by satellite phone.

The U.S.-allied Afghan forces have also brought in reinforcements, increasing their numbers from 500 to 800 soldiers, Hotak said.

He said hundreds of American troops were in Dai Chupan on Sunday, up from his earlier reports of up to 70 Americans. The U.S. military didn't confirm either number.

The coalition has 11,500 soldiers hunting down Taliban and Al Qaeda fighters, mainly in the south and east of the country.

The offensive against the Taliban in Dai Chupan was launched last Monday, when Afghan officials said U.S. warplanes bombed a mountain hideout near Dozai, killing at least 14 of the insurgents.

The fighting in Paktika province on Sunday came when U.S. troops patrolling northwest of the border town of Shkin came under attack from insurgents, the military said in a statement.

Three soldiers were wounded in the initial assault. A U.S. rapid reaction force was called in and a 90-minute firefight followed, the military said.

Two of the wounded soldiers later died, the military said.

The soldiers' deaths came after a U.S. special operations soldier was killed Friday in a fall during the fighting in Zabul province. A week earlier another U.S. soldier was killed in combat in eastern Afghanistan.

In all, 35 U.S. soldiers have been killed and 162 wounded in action in Afghanistan, the military said.