The Israeli military and Palestinian witnesses offered conflicting versions Tuesday of an airstrike in Gaza, as thousands of mourners called for revenge for the deaths of seven Palestinians purportedly killed in the attack.

Palestinians said the seven dead were civilians killed by an Israeli missile fired into a crowd at the Nusseirat refugee camp (search). The army said the majority of those killed were militants, releasing part of a video indicating there was no one on the street near the vehicle when it was hit by two missiles. The Palestinians say a third missile caused the deaths.

Brig. Gen. Ruth Yaron, the army spokeswoman, acknowledged there were civilian casualties, but added that "there is no doubt that the majority of those killed yesterday were terrorists." She held the militants ultimately responsible, saying they were using bystanders as human shields.

The airstrikes revived debate inside Israel over targeted killings in populated areas, and the Palestinian prime minister, in a rare criticism of Washington, complained that the United States was doing nothing to stop what he said are Israel's "ugly crimes."

In Washington, State Department deputy spokesman Adam Ereli expressed regret over the deaths of civilians and said Israel should consider the consequences of its actions. However, he said, if the Palestinians had stopped militants from firing rockets at Israel, "then perhaps Israel would not feel the need to act unilaterally in this way in its defense."

In Nusseirat, the flag-wrapped bodies of the seven Palestinians were carried on stretchers through the shantytown Tuesday.

"Sharon, wait, wait, you have opened hell's gate," the crowd chanted in a threat of revenge. Israeli Prime Minister Ariel Sharon (search) said Monday that Israel's war on terror would not let up.

Explaining the Nusseirat airstrike, the Israeli military said helicopters fired two missiles at a car carrying Hamas militants, and that two men inside were killed.

It said the helicopters had chased the car after the men dropped off two other militants near the border with Israel. Those attackers, who were killed by Israeli ground troops, were on their way to carry out suicide bombings inside Israel, the army said.

The army released a video showing two missiles hitting the car about a minute apart after a brief chase. No one appeared to be near the vehicle at the time of the missile strikes.

"We didn't see any massive gathering of people. We will not allow munitions to be launched when there is a massive gathering of people," said a senior air force officer, speaking on condition of anonymity.

The grainy video showed a crowd gathering around the car about two minutes after the second strike, and the video ended some 40 seconds later. The military said an additional 10 minutes were recorded but didn't release the additional footage.

A statement by Palestinian security said there were three missile hits, and those killed were struck by shrapnel from a missile fired after they had gathered near the vehicle.

Some witnesses said militants were able to flee the car after the first missile hit — which the video appeared to show caused only minor damage. The second missile caused more serious harm and, Israeli officials said, killed the militants inside.

But the images on the video were unclear so it was not possible to verify the witnesses' claims that the militants fled after the first strike.

But Palestinians said all of those killed were bystanders. They included an 11-year-old boy and a doctor who rushed to the scene to treat the wounded. Some 70 people were wounded, according to Palestinian medical officials.

Dr. Ibrahim Musader, director of the main hospital in nearby Deir al-Balah, said those killed were hit by shrapnel from the missiles.

An Associated Press reporter who reached the scene shortly after the attack Monday night saw several people with what appeared to be shrapnel wounds lying on stretchers and receiving treatment from paramedics.

More than a dozen ambulances were seen rushing from Gaza City (search) to the area of Nusseirat.

Within a half-hour of the missile strike, AP reporters saw dozens of wounded reaching the hospital in Deir al-Balah, some treated in the garden because there were no available beds.

Ambulances were called in to transfer some of the wounded to larger hospitals in Gaza City.

The Nusseirat attack was one of five Israeli airstrikes in the Gaza Strip (search) on Monday, one of the most intense single-day assaults with helicopters and warplanes in three years of fighting. Three more Palestinians — two Hamas militants and a bystander — were killed in the other strikes Monday.

Palestinian Prime Minister Ahmed Qureia (search) called for international intervention, referring to the airstrikes as "ugly crimes." Qureia complained that the United States is not intervening, saying he believes it was a "dangerous indication of the U.S. government's intention to abandon" its role in peace efforts.

The Palestinian leadership seldom criticizes the United States, seeking not to worsen an already troubled relationship with the most powerful international player in the region.

The missile hits also revived debate in Israel over targeted killings in crowded areas.

"Something terrible happened, and everyone should be sorry about this," said Interior Minister Avraham Poraz, a member of the centrist Shinui (search) party. "A pilot who is chasing after terrorists, if he sees that they are entering a crowd, it is better for him to give up. We will get them another time."

The seven victims in Nusseirat were identified by relatives as Mohammed Baroud, 11; Ahmed Khalife, 49, the owner of a local cement factory; Dr. Zain Shaheen, 29, a Ukrainian-trained doctor who rushed to the scene after the first missile strike to try to help; and university students Mohammed al-Masri, 26; Attiyeh Moaness, 20; Abdel Halim Tabassa, 23; and Mahdi Jarboua, 20.

Relatives said the seven all lived near the scene of the attack and were among the first to arrive.

Militants killed in Israeli strikes are usually claimed quickly by their organizations, but no armed groups came forward after the Nusseirat attack.

Monday's airstrikes came in response to the firing of homemade Qassam rockets (search) on Israeli border towns. A Palestinian ambush that killed three soldiers in the West Bank over the weekend may also have played a role in ordering the attacks, Israeli military correspondents wrote.

Three more Qassam rockets were fired into southern Israel late Tuesday, causing no injuries, the army said.

After nightfall Tuesday, Israeli forces surrounded a mosque about half a mile from Palestinian leader Yasser Arafat's office in Ramallah and questioned worshippers. In an exchange of gunfire, a Palestinian was seriously wounded.

Also, Israeli forces exchanged fire with gunmen in the Balata refugee camp next to Nablus. One Palestinian was lightly wounded, Palestinians said.