For Iraqis, the trouble began the next day. After a fairly relaxed occupation since the collapse of Saddam Hussein’s government on April 9, US soldiers in armored vehicles and Humvees, backed by helicopters overhead, moved aggressively to search homes — by residents’ count, more than 30 — in answer to the attack.

Iraqis said the soldiers who entered their homes that day, and talked to the women inside, crossed a line established by tradition and honor. Within a day, this conservative town on the Euphrates River 110 miles west of Baghdad, in a relatively well-off region that is mostly Sunni Muslims, became the scene of what seems to have been the first popular uprising against the US occupation.

By morning Wednesday, hundreds angered by the house-to-house searches had poured into the streets, marching to the police station whose officers had accompanied the soldiers. In a tumultuous scene, stones and a grenade were thrown, and US soldiers fired warning shots. By afternoon, the US troops withdrew. The crowd, having swelled to thousands, hauled the station’s furniture to a nearby mosque. Then they set the station on fire, hurling a few more grenades for good measure.

The two-story station, its windows shattered, still smoldered Thursday. An air-conditioner unit and an unhinged metal door were propped up against the entrance, blocking anyone from returning. On a wall, a slogan read, “God make this country safe.’’

“We will defend our houses, our land, our city,’’ said Salman Aani, 42, a businessman with an ice-making factory, dressed in a white robe. “We are Muslims, and we will defend Islam. The first thing we will do is defend our houses.’’

Since Sunday, five US soldiers have died in clashes and ambushes in the arc of territory that forms the heartland of Iraq’s Sunni Muslims, who were the basis for Saddam’s Baath Party. The US military has blamed the attacks on Baath remnants. But in Hit, along verdant fields and orchards criss-crossed by canals, the trouble seemed to revolve around the day-to-day details of occupation — an invader, however well-intentioned, unfamiliar with traditions running up against a fiercely conservative people infused with ideas of pride, dignity and honor.

Their traditions, the people of Hit said, were not respected.

“They are provoking us,’’ said Fawzi Saud, 46, a teacher whose house was searched Tuesday. “This is a violation of our dignity. They have no right to enter our house and search it. I’m not a soldier, I’m not a policeman, I’m not a party member.’’

US soldiers, stationed a few miles outside town, said they were baffled by the unrest. When they arrived, they said, people waved and shouted hello. As the weeks dragged on, those greetings were fewer, occasionally replaced by rocks.

By late afternoon Thursday, they had not returned to the town of 25,000, asking journalists about the mood in Hit and the status of the police station.

“I couldn’t speculate as to what the cause of the anger in the town has been,’’ said Capt. Andrew Watson, a staff officer with the 3rd Squadron of the 3rd Armored Cavalry Regiment. “For us to say it was one thing or another would be for me speculation.’’

He and other soldiers said their intent was never hostile. They said they had gone to great efforts to speak only to the men and avoid being too intrusive with the searches that followed the rocket-propelled grenade attack.

“The golden rule applies here,’’ Watson said, “just like it does anywhere else.’’

“We try to be as culturally sensitive as possible, but we want to make sure everybody goes home alive,’’ said an intelligence officer. “We’re not going to risk the lives of one of our soldiers to be culturally sensitive.’’

Residents blamed the eruption of unrest on the search of a particular house Wednesday morning, the second day of inspections. They said a tank, three armored vehicles and a jeep pulled up to the one-story home of a widow with three daughters and a son. The 14-year-old son was in school, but the soldiers, accompanied by two Iraqi policemen, entered anyway. They stayed for 90 minutes.

“Nobody knows why,’’ said Khaldun Saud, a 51-year-old neighbor. “They didn’t find anything, no weapons, nothing.’’

Neighbors heard the woman start yelling, apparently frightened. After the Americans left, a friend took the woman and her daughters to a relative’s home. But word of the search raced through the tightly knit community, and within minutes, the crowd began marching on the station.

“We consider the city one family,’’ said a neighbor, Tareq Deham, 55.

Iraqis gathered at the police station Thursday said they had put their demands in writing at the station, but given the chaos, never had a chance to deliver them. The demands were blunt: The Americans had to withdraw from the town, they could no longer search homes, particularly with women inside, and the police — employed under Saddam’s government — had to be replaced.

Thursday afternoon, neighbors gathered in the house of Fawzi Saud, Khaldun’s brother. They traded stories that were perhaps rumor, perhaps fact, in seeking to explain the uprising.

Soldiers, they said, entered homes without knocking, and they kept their finger on the trigger. In the early morning, helicopters had flown low overhead, they said, allowing soldiers to see families sleeping on their roofs to escape the summer heat. No rooms were left unsearched, the Iraqis said, including bedrooms. All these actions, they complained, violated their sense of what is right.

Five soldiers entered his home at 10:30 a.m. Tuesday, Fawzi Saud said. He was not home, but his 20-year-old son, Ahmed, was. When the soldiers knocked, Ahmed asked them to wait, Saud recalled. They did not and three soldiers entered with two policemen, he said, and the others circled behind the house.

They stayed for 10 minutes, checking the six rooms. Throughout the search, Saud’s 11-year-old daughter, Taysir, cried, he said. Ahmed said no weapons were found. An AK-47 assault rifle — a possession of virtually every family in the town — was hidden outside, but his father would not say where.

The Americans, Saud said, are no longer guests.

“They’re going to stay a long time, if they have it their way,’’ he said. “But the people will refuse. They won’t tolerate it.’’

Everyone in the modest room, with an unadorned cement floor, nodded in agreement. “We’re not hostile people,’’ he explained. “We don’t make any trouble. But if the Americans are hostile to us, we’ll be hostile to them.’’