Updated

U.S. jets pounded Afghanistan's eastern mountains Friday, flooding valleys and hideouts near Usama bin Laden's Tora Bora cave compound with thick dust and smoke.

Local tribes believe bin Laden may be in the midst of the relentless bombing. Local commanders claim to have overheard a tall man on horseback near Tora Bora inquiring in Arabic about "the sheik," which the commanders believe to be a reference to the Al Qaeda leader.

Hundreds of anti-Taliban forces have been attacking the compound this week in an attempt to rout out Al Qaeda fighters who retreated to the complex of tunnels and caves as the Taliban was pushed out of most of Afghanistan.  The anti-Taliban forces have also been driven in their manhunt by the $25 million reward on bin Laden's head. 

Gen. Tommy Franks, commander of the U.S. operation in Afghanistan, said American forces were working with local anti-Taliban militias and the Pakistani government to prevent senior Al Qaeda members from escaping across the border. He noted U.S. special forces were in the area.

"We are in coordination with Pakistan as well as with opposition forces to do the best we can in this terribly rugged terrain to prevent the escape of those leaders," Franks told reporters in Tampa, Fla.

Local commanders said Arab fighters had abandoned their main caves as the bombardment and ground attacks intensified, and had moved with their entire families into smaller caves higher in the mountains. Between airstrikes, fighters reported seeing the children of Arab guerrillas playing outside caves.

The Al Qaeda fighters rained mortar shells, rockets and bullets from their mountaintop positions, firing at pickup trucks packed with tribal fighters heading to and from the front lines. Tribal fighters responded with tank fire and mortar bombardments.

One of the commanders, Zein Huddin, said Friday night that his forces had intercepted Arabic-language radio traffic between the fighters in the mountains and allies in Kandahar before the Taliban abandoned the southern city.

"We have intercepted radio messages from Kandahar to the Al Qaeda forces here, and they ask, 'How is the sheik?' The reply is, 'The sheik is fine,"' Huddin said. He was convinced "the sheik" was none other than bin Laden.

Another senior commander, Haji Kalan Mir, said his men reported seeing a man who resembled bin Laden on Friday, riding on horseback at the front line with four deputies.

"He went riding back to (the village of) Malaewa after visiting some of his troops," Mir said.

A third commander, Haji Musa, said he didn't know about bin Laden, "but his son is still in the caves."

None of the reports could be independently confirmed, and U.S. officials say they are getting so many bin Laden sightings they don't know which are valid.

"I see, literally, dozens and dozens and dozens of pieces of intelligence every day, and ... they don't agree," Defense Secretary Donald H. Rumsfeld said Thursday when asked whether bin Laden was near Tora Bora. "One can't know with precision until the chase around the yard is over."

Nonetheless, the American military has focused intense bombing in the remote mountains near the Pakistani border. One tribal fighter said Friday that he was assigned to protect 20 U.S. Navy personnel coordinating airstrikes from the ground and that they were living in a schoolhouse at a nearby village.

A senior Pentagon official, Gen. Peter Pace, said special operations troops have started working with the tribal fighters in the area, relaying information to warplanes that can be used to determine bombing targets.

Commanders said there was no hand-to-hand fighting Friday, as there had been a day earlier when the tribal fighters seized two caves — and then pulled back to allow U.S. warplanes to soften Al Qaeda positions before attacking again.

"Today we didn't do much, we didn't have an attack plan," said Hazrat Ali, one of three commanders attacking the mountains. He planned a major push on Saturday.

Ali said three of his men had been killed since Tuesday, when the assault began.

The Qatar-based television network Al-Jazeera reported Friday that the Arabs had asked for a five-day break in the fighting to leave the area. It gave no details, and both the United States and Afghanistan's new administration have said foreign fighters in Afghanistan must be brought to justice.

That appeared to leave the Arabs with little option but to fight. The only trails out — across the border with Pakistan — were covered in deep snow.

During Friday morning prayers, a Muslim cleric from the Arabs' side called out over a loudspeaker to the tribal fighters across the front line. He pleaded with his "Muslim brothers" to cease their attack, asking them instead to send in the Americans.

The village of Tora Bora, which means "black dust," lent its name in the 1980s to one of the most well-known anti-Soviet guerrilla bases, which was carved into the side of Ghree Kil mountain with U.S. funding.

The Associated Press contributed to this report.