The attack was the first to target American officials since the latest Israeli-Palestinian violence erupted three years ago.
The bomb detonated around 10:15 a.m. local time as the convoy, escorted by Palestinian police, headed south on the main road just after entering the Gaza Strip. In Washington, State Department spokeswoman Brooke Summers said the blast came from a “previously planted explosive device.”
Wednesday’s bombing was the first time that a convoy of U.S. diplomats had been targeted in Israel or the Palestinian territories since the latest round of violence began in September 2000.
Palestinian militant groups Islamic Jihad, Hamas and the Popular Front for the Liberation of Palestinian denied involvement in the attack.
The blast gouged a deep crater into the unpaved road and tore the van in half, flipping the wreckage over. The nearby ground was stained with blood and littered with flesh that Palestinian paramedics collected.
After the convoy’s first two cars — including the police escort — drove by, the bomb detonated as the third car passed, witness Mohammed Radwan told the Associated Press.
“The first two cars drove quickly and stopped far from the explosion. Palestinian security people jumped out of the car and rushed to the car that had blown up. … I saw two people covered with blood lying next to the car,” Radwan said.
The U.S. State Department said the three dead were security personnel accompanying Tel Aviv-based U.S. diplomats on their way to interviews with Palestinian Fulbright scholarship candidates.
U.S. convoys travel regularly in Gaza and often take the same route along a main road in easily identifiable vehicles that usually bear diplomatic license plates.
Palestinian leader Yasser Arafat called the attack an “awful crime” and said he ordered an investigation.
Palestinian Prime Minister Ahmed Qurei also denounced the bombing and pledged to find those responsible.
“We strongly condemn this incident and we will conduct an investigation and we will follow it to find the source of this attack,” he told reporters in the West Bank.
Israel said the attack emphasized the need for Palestinian officials to crack down on militant groups.
“This is further proof that as long as the Palestinian Authority does not dismantle terrorist organizations, the process will not proceed,” Foreign Minister Silvan Shalom said in a statement.
U.N. Middle East envoy Terje Roed-Larsen called the attack an “ominous widening of the conflict” and said it “underscores the vital need for the Palestinian Authority to revamp and strengthen its security forces so such terror attacks do not occur.”
Secretary of State Colin Powell urged the Palestinian prime minister to act against militants in a phone call made after Wednesday’s bombing.
“Mr. Powell told the prime minister it was important that the Palestinian Authority take action to put an end to violence and ‘terrorism’,” Hassan Abu Libeh, the head of the prime minister’s office, told Reuters.
Several hours after the attack, U.S. investigators arrived at the scene and photographed the mangled van but Palestinian youths throwing stones at the team forced them back to their cars and they drove away.
U.S. Ambassador to Israel Daniel Kurtzer told reporters that the Federal Bureau of Investigation will send a team to the Gaza Strip to investigate the bombing.
Kurtzer also called on the Palestinian Authority to capture the bombers and said the United States would continue working toward peace in the region despite the unprecedented attack.
In response to Wednesday’s attack, the U.S. embassy in Tel Aviv advised all Americans to leave the Gaza Strip for their own safety.