Somali Blasts Stir Fear That U.S. Is Target : Africa: Six Americans are slightly injured when a remote-controlled bomb detonates under their truck, the third ambush in two weeks. Officers say warlord’s guerrillas may be singling out U.S. troops.

In an attack that intensified fears that Somali guerrillas are targeting U.S. soldiers, six Americans were slightly injured Sunday when a remote-controlled bomb was detonated as their supply truck drove on one of the busiest roads of the capital, Mogadishu.

The attack, the third in two weeks, appeared to document what several American commanders serving in key slots of the U.N. operation in Somalia have suspected since the first attack killed four Americans Aug. 8--that militiamen loyal to renegade Somali warlord Mohammed Farah Aidid are singling out the American contingent in the multinational coalition authorized to restore order in Somalia.

“If you ask me, ‘Are they targeting Americans?’ I would say, ‘Probably,’ ” U.S. Army Gen. Norman Williams, deputy commander of the 4,000 American troops serving in the U.N. operation in Somalia, said in an interview with The Times last week. “There’s very little we can do about these attacks. It’s the mines, the explosive devices, that are so hard to deal with.”

But although he and other American commanders say it is virtually impossible to defend against such attacks, they insist that the dangerous patrols must continue if the United Nations is to succeed in its mission to pacify and rebuild this ruined nation.

“We have to go on those roads. We can’t just sit in the compounds,” Williams said in the interview a few days before the most recent incidents.

Sunday’s attack came just days after four Americans were injured when their truck hit a land mine Thursday.

In the incident Sunday, the convoy was approaching the port on one of Mogadishu’s most heavily traveled streets when the explosion ripped the undercarriage of a 2.5-ton truck. Like most U.S. trucks in Somalia, it had been reinforced with steel plating and was carrying sandbags in its bed as protection against mines.

The six Americans in the vehicle suffered only minor cuts and bruises, U.N. military spokesman Tim McDavitt told the Associated Press.

Gen. Williams, who commands the vast U.S. Army logistics operation that is delivering fuel, water and other military supplies to the coalition force of more than 25,000 troops scattered throughout the capital and the countryside, said his troops cannot abandon their mission in the face of Aidid’s mounting urban guerrilla war.

“We’ve gone with the strategy that we can’t just sit back and let Aidid do these things to stop us from doing our job,” Williams said.

The United Nations blames Aidid for the murder of 24 Pakistani peacekeepers in June and the continuing attacks on U.N. forces. Aidid insists that the later attacks are retaliation for U.S. air strikes on his compounds and arsenals in June and July.

Williams and other commanders acknowledged that the attacks have hindered the U.N. mission, forcing the peacekeepers to commute to work by time-consuming and costly helicopter shuttle flights and confine all road trips to “mission-essential” travel. And they said that it is the U.S. troops who must carry out most of those mission-essential operations.

“Our job is to keep the fuel, the water, the field rations and equipment flowing to all the regions, plus to the contingents here in Mogadishu,” Williams said, adding that about 30 of his troops have been injured since the United Nations took command of the Somalia mission from U.S. Marine commanders May 4.

“We are the front line here.”

As a result, U.S. military police patrols must scout out the main supply routes in the city and countryside each day to determine their safety before the Army’s transport companies roll out of their besieged warehouses on supply runs.

It was during one such patrol that Aidid’s forces inflicted the deadliest single attack on American forces since the U.S. Marines landed in Mogadishu last December.

An investigation into the Aug. 8 ambush, which was initially blamed on a land mine, disclosed that Aidid’s forces had packed plastic explosives into a relatively sophisticated device connected to a battery-powered detonator.

Although the military police have continued their patrols, their commander conceded that the first attack--in which three of the victims had arrived in Mogadishu just two days before--had a devastating impact on the troops.

“It has an effect on morale,” said Capt. Chris Nelson, commander of the 977th Military Police Company, which is the cutting edge of the Army’s supply operation. “It has a shocking, sobering effect when it happens so early in a mission.

“The only thing you can do is work together as a team to get through it.”

When asked, however, what can be done to minimize future such attacks, Nelson shook his head.

“This kind of incident is undefendable. It’s a terrorist act,” he said, adding that his company was “briefed extensively” on the threat of land mines before leaving the United States but that few expected Somalia’s warring clans to use more sophisticated explosive devices.

“But we are the most exposed--out on the streets every day. And the best advice we got is just stay awake. Keep alert.”