Washington The rules for a cave assault: Strike fast and hard, keep the enemy off balance, use four-man teams and advance quickly from room to room.
A U.S. military expert said those are the type of tactics likely to be used by American commandos and anti-Taliban Afghan rebels advancing on the Tora Bora and other cave and tunnel complexes where Osama bin Laden and other al-Qaida leaders are suspected of hiding.
"We try to rely on speed," says Army 1st Sgt. Alexander Somoda, a Ranger and combat veteran from Panama and Iraq who now trains infantry troops in urban combat at Fort Lewis, Wash. "You want to hit them hard. You knock him back on his heels."
Laying out the tactics for an assault, he says to watch for traps once inside a cave and prepare for casualties it's hard to miss when armed men are shooting at point-blank range.
"If the enemy is very clever, there's a certain point you're going to lose a few people," says Somoda, who trains infantrymen in urban combat in one of the Army's new lightweight brigades at Fort Lewis, Wash.
An estimated 1,500 Afghan tribal fighters, aided by U.S. commandos, are advancing down a valley near the Tora Bora complex in the White Mountains south of Jalalabad.
It's unclear how much close-quarters tutelage that U.S. forces may have provided, but it's among the instruction Green Berets are trained to give, Army Special Forces spokesman Maj. Gary Kolb said.
Much of America's high-tech superiority would be lost in a direct cave assault. No air support, no computers, no satellite aid. Caves are too dark for night-vision goggles to be effective. The troops must rely on gun-mounted flashlights to see.
To some, waiting out members of the al-Qaida network is a safer course of action.
"They should lay siege, rather than go in and fight for every inch it's not worth it," said Ali Jalali, a former Afghan colonel who fought with the mujahedeen against the Soviet Union.
An Army company about 150 soldiers would be assigned to a cave complex. After confronting guards outside the cave, the unit would then move to isolate the entrances, preventing escape and reinforcement.
Stationed outside, soldiers with mortars, heavy machine guns and sniper rifles would fight off any approaching enemy forces. Then, squad by squad, the rest of the team would go in.
A nine-man squad would advance toward a particular section of the cave. Most would have a smaller version of the M-16 assault rifle. Two troopers would have heavy-duty automatic rifles with magazines holding 200 rounds. Two more would have rifle-mounted grenade launchers. Special operations commandos also would have shotguns.
Somoda says the goal is to move swiftly and prevent the enemy from organizing. But as the soldiers advance, they risk triggering a trap probably a tripwire that springs a grenade.
He advises his troopers to stay alert, watch for anything that catches their eye: "If there's something that makes you look up, you better look down."
While U.S. intelligence officials are skeptical of reports of the massive underground complexes, they describe small networks of caves, chambers and hallways built into several mountains outside Jalalabad.
Some of these redoubts were financed with CIA money