U.S. special operations troops combing Iraq for Scud missiles and chemical or biological weapons have found none so far, a senior American military officer said Saturday.

Maj. Gen. Stanley McChrystal, the vice director of operations for the Joint Chiefs of Staff, told a Pentagon news conference that the Iraqis have not fired any Scuds and that U.S. forces searching airfields in the far western desert of Iraq have uncovered no missiles or launchers.

Iraq denies having any Scuds, which have sufficient range to reach Israel, but Gen. Tommy Franks, who is running the war, said Saturday that Iraq has yet to account for about two dozen Scuds that United Nations inspectors have said were left over from the 1991 Gulf War.

Iraq also denies it holds any chemical or biological weapons. McChrystal said the United States will either bomb any such weapons it should find or seize them with ground forces, whichever is safer. He and other officials refused to say where in Iraq those searches are happening.

Also Saturday, the U.S. military abandoned plans to open a northern front against Iraq that would have sent heavy armored forces streaming across the Turkish border.

Two U.S. defense officials said dozens of U.S. ships carrying weaponry for the Army's 4th Infantry Division will head to the Persian Gulf after weeks of waiting off Turkey's coast while the two countries tried to reach a deal.

McChrystal said that even without the 4th Infantry, "there will be a northern option." He would not say what that might be. Other officials said Army airborne troops might join small numbers of U.S. special operations forces already on the ground in northern Iraq, where American officials fear clashes between Turkish forces and Iraqi Kurds.

Although U.S. officials on Friday said all 8,000 soldiers in Iraq's 51st Mechanized Division in southern Iraq has surrendered, McChrystal said Saturday that only the unit's commanders gave themselves up. The rest simply left the battlefield or were "melting away," he said.

McChrystal said the number of Iraqi prisoners of war was between 1,000 and 2,000.

In describing overall progress in the war, McChrystal said American and British forces have hit Iraq with 500 cruise missiles -- 400 launched from ships and submarines and 100 launched from Air Force bombers -- and several hundred precision-guided bombs over the past day. The use of air-launched cruise missiles in Friday's attacks was the first since the war began.

Warplanes flew 1,000 missions from aircraft carriers and air bases in the region, he said.

Iraqi soldiers, "including some leadership," are surrendering and defecting in large numbers, Pentagon spokeswoman Torie Clarke said.

"It is only a matter of time before the Iraqi regime is destroyed and its threat to the region ... is ended," she said.

Northern Iraq is an important battleground because of the Kurdish presence in enclaves not controlled by the Iraqi government. Turkey fears the Kurds will seize the northern oil fields or establish an independent state, thus complicating Turkey's conflict with its own Kurdish minority.

The Pentagon wanted to put a heavy armored force into northern Iraq and had designated the 4th Infantry for that mission. The only feasible avenue for them to reach northern Iraq was from bases in Turkey, an option foreclosed by the Turkish government.

With U.S. ground forces advancing toward Baghdad, Pentagon officials expressed concerns the troops might come across Republican Guard troops armed with chemical weapons.

"We would be hopeful that those with their triggers on these weapons understand what Secretary Don Rumsfeld said in his comments yesterday: ‘Don't use it. Don't use it,"' Franks, the top U.S. war commander, said Saturday at a news conference at his Persian Gulf command post.

The administration had once believed it could count on NATO ally Turkey to support the creation of a northern front against Iraq. But after weeks of wrangling over financial compensation and arrangements for Turkish forces to join the Americans in northern Iraq, the Pentagon has given up.

The Turkish military on Saturday denied reports that 1,000 of its commandos had crossed into northern Iraq. On Friday a military official had said soldiers in armored personnel carriers rolled into northeastern Iraq near where the borders of Turkey, Iraq and Iran converge.

But on Saturday that was denied, and Pentagon officials said they saw no sign of a Turkish incursion.

About 40 ships carrying the 4th Infantry Division's weaponry and equipment were to begin moving through the Suez Canal on Sunday, said one U.S. official, speaking on condition of anonymity.

The 4th Infantry's soldiers, who remained at Fort Hood, Texas, after their weaponry and equipment went to the Mediterranean last month, are likely to go to Kuwait, the officials said.

The redirected cargo ships are to begin arriving off the coast of Kuwait about March 30, one official said. All the ships would arrive by about April 10.

From Kuwait they could move into Iraq to serve as reinforcements if the ground war lasts more than several weeks, or as occupation forces after the Iraqi government's collapse.