FALLUJAH, Iraq (AP) _ U.S. troops opened fire on anti-American demonstrators for the second time this week as Iraqis marched Wednesday to protest the previous shooting. The local hospital said one person was killed and at least 16 others wounded.

The gunfire came less than 48 hours after a shooting during a demonstration Monday night that hospital officials said killed 13 Iraqis. There was no immediate indication of any American casualties.

The clashes in Fallujah, a conservative Sunni Muslim city and Baath Party stronghold 30 miles west of Baghdad, reflect the area's increasing tensions as American troops try to keep the peace in Iraq.

About 1,000 residents marching down Fallujah's main street stopped in front of a battalion headquarters of the U.S. Army's 82nd Airborne Division, in a compound formerly occupied by Saddam Hussein's Baath Party. The demonstrators were carrying signs condemning Monday night's shooting.

Protesters started throwing rocks and shoes at the compound and troops opened fire about 10:30 a.m., scattering the demonstrators. Protesters then returned to pick up the wounded.

Medical staff at the Fallujah hospital said a 30-year-old man was killed, another man was in critical condition and 15 others were wounded.

Maj. Michael Marti, an intelligence officer for the division's 2nd Brigade, said soldiers in a passing convoy fired on the crowd after rocks were thrown at them and a vehicle window was broken by what was believed to be automatic weapons fire.

As the convoy was passing, the demonstrators ``started throwing rocks and then at one point, they (soldiers) were engaged by what they believed was an AK-47'' and opened fire, said Marti, of Archbold, Ohio.

Capt. Jeff Wilbur, a civil affairs officer, said the fire from the convoy was followed by soldiers opening fire from the compound.

City officials who witnessed the gunfire said they saw or heard no shooting from among the protesters.

U.S. Apache attack helicopters circled the site throughout the march and for hours afterwards. U.S. officers met with Fallujah mayor Taha Bedaiwi al-Alwani and leading area sheiks in hopes of reducing the tensions, while several dozen demonstrators clustered angrily outside the town hall.

``Get out, get out!'' one protester shouted at soldiers guarding the meeting.

``We will keep this up, we will keep them on edge,'' said another protester, 29-year-old Abdul Adim Mohammed Hussein.

Emerging from the meeting, the imam of the Grand Fallujah Mosque, Jamal Shaqir Mahmood, said ``The Americans said 'we won't reduce the numbers, they're needed for security.' But the people of Fallujah told them we already have security.''

The American forces have given no indication they might reduce their presence in Fallujah, the site of factories suspected of being linked to banned weapons programs for Saddam's regime. However, U.S. forces did leave their station at the school where Monday's shooting took place.

Americans and Iraqis have given sharply differing accounts of Monday night's shooting. Paratroopers from the 82nd Airborne said they opened fire only upon armed men _ about 25 infiltrators among a crowd of 200. Protesters insisted their demonstration was unarmed and peaceful.

Dr. Ahmed Ghandim al-Ali, director of Fallujah's general hospital, said the clash Monday killed 13 Iraqis _ including three young boys _ and injured about 75. Some residents put the death toll higher, at 15.

No Americans were injured.