Baghdad, Iraq ? L. Paul Bremer, the U.S. civilian administrator for Iraq, said Saturday that military experts have drawn strong links between al-Qaida and other terrorist groups and the guerrilla attacks that have killed 59 U.S. soldiers since May 1 when President Bush declared the end of major combat operations.

Iraqi insurgents killed a U.S. soldier and injured three others late Friday night despite stepped-up efforts by American forces to find and disarm increasingly diverse resistance groups.

Bremer said four groups are behind most of the attacks: Baath Party loyalists, remnants of the irregular Saddam Fedayeen force, intelligence officers from the former regime and foreign fighters. A senior administration official in Washington added a fifth group: common criminals.

The foreign element, Bremer said, includes al-Qaida and Ansar al Islam, a militant Islamic group that U.S. and Kurdish forces attacked in northern Iraq during the war but is now believed to be restructuring.

“With regret, I say we did not kill all of them,” Bremer said. “Some of them escaped to other countries and are now trickling back in.”

Senior administration officials in Washington, speaking on the condition of anonymity because intelligence matters are classified, said the foreigners include Syrians, Saudi Arabians, Jordanians, Yemenis, Pakistanis and even a few Albanians.

Two things are most worrisome, one intelligence official said: Many of the foreign fighters appear to have been trained in terrorist or guerrilla tactics, and none of them appears intent on restoring Saddam to power. Most of the foreigners, in fact, are Islamic militants who cheered the fall of the secular Iraqi regime, the official said.

“The danger is that some of these guys want to make Iraq the next Afghanistan or Somalia or Chechnya, the next battleground between Islam and the infidels. Getting rid of Saddam and turning the electricity back on won’t do anything to change that.”

In one case that suggests that militant Islamists far from Iraq may be joining the fight, Algerian intelligence officials recently told their French counterparts that they’d detected members of a new militant group, calling itself al Taifa al Mansouri, or the chosen and victorious, heading to Iraq to kill Americans. French officials relayed the warning to their American counterparts.

After being transported by helicopter to patrol the area of al-Alrisala, Iraq, 50 miles south of Mosul, soldiers with the 101st Airborne Division cover their faces to protect themselves from the sand. Experts have found strong links between al-Qaida and the guerrilla attacks that have plagued U.S. troops patrolling in Iraq.

Saddam, however, remains a factor. He promised to return to power and reward Iraqis who refused to help American forces, according to an audiotape aired Friday on an Arabic-language television station. The voice on the tape could not immediately be verified as Saddam.

U.S. officials are still hunting the former leader, and released computer-generated photos Saturday that depict Saddam in possible disguises ranging from a tribesman in traditional dress to an elderly white-aired man.

Bremer praised the Iraqi informant who turned in the former dictator’s sons, Odai and Qusai, and reminded residents of the $25 million bounty on Saddam’s head. Saddam’s sons and teenage grandson, all killed on July 22 in a raid by U.S. forces, were buried Saturday by tribal members and other relatives on the outskirts of Tikrit, their ancestral hometown.

The man who told U.S. forces Odai and Qusai were staying in his home in the northern city of Mosul received $30 million and asylum outside Iraq. Since then, Bremer said, many more Iraqi informants have come forward.

“We’re going to get Saddam, too,” Bremer said. “The only question is: Who’s going to get the $25 million and move to another country?”

Throughout Iraq, U.S. convoys continue to be targets, and officials in Washington told Knight Ridder that the administration has asked Turkey to send three brigades of troops, some 15,000 men, to help patrol western or central Iraq.

The Turks, the official acknowledged, could not be used in the north because the Kurdish population there distrusts them or in the south, where Iraqi Shiite Muslims wouldn’t welcome foreign Sunni Muslim soldiers. Turkey, the officials said, is considering the request, and whether to send any troops without a new United Nations resolution.

A 4th Infantry Division soldier was killed and three others were injured around 10 p.m. local time Friday when a rocket-propelled grenade hit their convoy about 13 miles west of Hamajah, a small village about 50 miles northeast of Baghdad.

In a separate incident the same evening, an Iraqi woman near the scene of an attack in Baghdad died from shots fired in self-defense by U.S. troops. Guerrillas had dropped an explosive device onto a six-vehicle convoy from a highway overpass — a technique used last week in an attack that killed a soldier and injured three others.

Another U.S. soldier died at about 7:30 p.m. local time Thursday, the night most Iraqi weddings take place, after he was struck by gunfire from a celebrating Iraqi man.

A large section of Baghdad was cordoned off on Saturday morning as U.S. forces defused an improvised explosive device found in a busy shopping district frequently patrolled by U.S. troops. Several other potential attacks were prevented this week when U.S. forces conducting raids in several towns found artillery rounds, six surface-to-air missiles, rocket-propelled grenades and many smaller weapons, according to military officials.