WASHINGTON — U.S. warplanes mistakenly bombed Red Cross warehouses and a nearby residential area in Kabul for the second time in a month, the Pentagon acknowledged Friday.

In separate raids late Thursday and early Friday, F/A-18 jets dropped two one-ton bombs on the Red Cross warehouse complex, the Defense Department said in a statement. Two B-52 Stratofortress bombers each dropped three one-ton bombs on the same complex, which was mistaken for a Taliban military warehouse.

During Thursday night's attack, an F/A-18 tried to hit the warehouse complex with a 500-pound bomb that landed in a residential area about 700 feet away, the Pentagon said. That bomb's guidance system may have malfunctioned, the statement said.

The Defense Department said that "preliminary indications are that the warehouses were struck due to a human error in the targeting process.''

``Two of the six warehouses hit had been inadvertently struck by U.S. aircraft on Oct. 16 because the Taliban had used them previously for storage of military equipment, and military vehicles had been seen in the vicinity,'' the statement said.

The Red Cross reported that no one was injured in the latest mistaken bombing, the Pentagon said.

President Bush said Friday that U.S. airstrikes are gradually eroding the Taliban's military strength and setting the stage for defeat of the shadowy al-Qaida terrorist network.

Bush spoke on the 20th day of airstrikes aimed at bringing down the radical Islamic Taliban regime and rooting out the al-Qaida terrorists believed to be linked to the Sept. 11 terrorist attacks.

``We're slowly but surely dismantling Taliban defenses, Taliban military installations, the Taliban command and control structure — all aimed at bringing the al-Qaida criminals to justice,'' the president said in a speech to business, trade and agricultural leaders at the White House.

Bush urged Americans to be patient as the U.S. military, with support from Britain and other allies, carries out a carefully drawn strategy that combines air power with less visible special operations on the ground.

The British government announced it will commit 200 special forces troops to the offensive in Afghanistan, as part of a larger force that will include warships and planes. Indicating that a long campaign is expected, Armed Forces Minister Adam Ingram told Parliament that 200 commandos of the Royal Marines would be based on assault ships in the region. Another 400 will be on standby in Britain, he said.

At the Pentagon, a senior officer briefed reporters on the military campaign and welcomed the British contribution, but would not discuss how or when the Royal Marines would be used in Afghanistan.

The officer, Rear Adm. John Stufflebeem, said U.S. warplanes had struck a variety of military targets on Thursday, including cave complexes believed to contain Taliban or al-Qaida fighters. Among the weapons used Thursday were a small number of Tomahawk cruise missiles, which have been fired only sparingly since the early days of the military campaign.

In keeping with Pentagon practice, Stufflebeem offered information only about the previous day's air missions and said nothing of what happened Friday. Other officials, speaking on condition of anonymity, said Friday's attacks against Taliban positions north of Kabul and elsewhere were carried out by roughly 50 strike aircraft, compared with about 80 planes used in the previous day's attacks.

The Air Force continued airdropping thousands of food rations to starving Afghans, and U.S. planes dropped leaflets and broadcast messages informing Afghans of the humanitarian assistance.

Bush spoke confidently of winning what he called the first battle in the war on terrorism, but he also cautioned that the fight requires determination — not just by the military but by the public as well.

``The American people are going to have to be patient, just like we are,'' Bush said. ``They're going to have to be determined, just like our military is. And with that patience and with that determination, we will eventually smoke them out of their holes and get them and bring them to justice.''

Though some American allies in the region with radical Muslim factions would like the campaign finished soon, the Pentagon has said from the beginning that it would take time — and more than an air campaign — to get Osama bin Laden.

Stufflebeem took issue with suggestions that the U.S. military is bogged down.