RAMALLAH, West Bank ? Trapped in their homes by shelling and gunfire, they’re running short of food and water, soothing their fearful children and  in at least one case  dying in a hail of gunfire.

They’re American citizens in Ramallah, one of the half-dozen West Bank towns that have come under Israeli military control in the past six days.

About 16,000 Americans live in and around Ramallah, the largest and most important of the Palestinian towns seized by Israel as part of a military offensive that Prime Minister Ariel Sharon says is meant to crack down on terrorists.

These are dangerous days for U.S. citizens on both sides of the Israeli-Palestinian divide. The State Department advised American residents of Jerusalem to leave after it was hit by a relentless wave of suicide bombings aimed at Israelis.

Thousands of Americans are also among the 200,000 Jewish settlers in the West Bank and Gaza Strip, who have frequently been targeted by Palestinian gunmen during 18 months of bitter Israeli-Palestinian conflict.

Of the U.S. citizens living in Ramallah, nearly all are Palestinian-Americans. Many had an American upbringing or education, but returned because of family ties, or out of a desire to see their children learn Arabic and absorb Palestinian culture.

Because so many people have U.S. family connections, Ramallah has long had a strongly American flavor. English is widely spoken, there are burger joints and Internet cafes, and the town is the headquarters for the Palestinian franchise of Coca-Cola.

The fighting of these past months has touched the lives of almost everyone, Israeli or Palestinian, but for those in Ramallah, the Israeli offensive that began when tanks rumbled into town last Friday has been a particularly harsh reminder of the conflict’s realities.

Hala Abdallah, a 37-year-old native of Detroit, awoke the next morning to the sound of truck-mounted loudspeakers blaring instructions in Arabic for all boys and men between the ages of 14 and 40 to come outside. As they have elsewhere, Israeli troops were rounding up fighting-age men to try to snare fugitives wanted for attacks against Israelis.

Abdallah and her husband, Fayyad, decided they had better wake up their son Nidal, a gangly 11th-grader. He is an American citizen, born in Cicero, Ill.

“I didn’t want to send him out, but neighbors said, ‘You should, or soldiers will break in and search the house,”‘ Hala Abdallah said. “So he walked outside with his father.”

Troops instructed Nidal to lift up his shirt  Palestinian males rounded up in this fashion are obliged to show they are not wearing an explosives belt or carrying a weapon  and then he was marched away. His father, who is 52, was not allowed to accompany him.

“The neighbors said, ‘Oh, you’re Americans, they’ll send him right home,”‘ Hala Abdallah said. “But they didn’t.”

Nidal, who is 17, was held overnight in a schoolhouse, one of about 70 boys packed into a single classroom. They were given no blankets or bedding, his mother said.

His parents, too, spent a sleepless night, and deflected the questions of Nidal’s sisters, 8 and 13, who wanted to know when he was coming back. In the morning, he returned, tired and hungry, and tried to comfort his distraught mother.

“He’s at that age where he wants to be a man and handle things, but I hated for him to go through something like that,” she said, still tearful days later.

Another U.S. citizen, 21-year-old Suraidah Abu Gharbiah, was among the first fatalities of the Israeli incursion into Ramallah. Doctors said she was shot while riding in a car with her husband and 9-month-old son.