After a car bomb exploded Saturday at a U.S. military checkpoint in central Iraq killing four American soldiers, the Iraqi vice president said that coalition forces could expect more suicide attacks.

The car bomb exploded just north of the small city of Najaf, not far from the furthest forward positions that U.S. troops have reached in the 10-day-old war against Iraq.

According to witnesses, a taxi stopped close to the checkpoint, and the driver appeared to wave for help. As soldiers approached the car, it exploded. The victims were part of the Army's 1st Brigade, 3rd Infantry Division.

Iraq promises more attacks

The Iraqi government said Ali Hammadi al-Namani, a junior army officer, had carried out "a martyrdom operation" and that President Saddam Hussein had awarded him two posthumous medals.

"It's the blessed beginning," said a statement released by the Iraqi government, alluding to the suicide attack. "He wanted to teach the enemy a lesson in the manner used by our Palestinian brothers."

Iraqi Vice President Yassin Ramadan said there will be more suicide attacks in the weeks ahead.

"Any method that stops or kills the enemy will be used. What are they doing in our land? Let them pack and go," he told a news conference.

"The United States will turn the whole world to martyrs against it. What do they expect? The Arabs and Muslims are not allowed to develop missiles and bombs as powerful as theirs," Ramadan said.

Thousands of Arab volunteers were arriving in Iraq to fight the invading U.S. and British forces, he added.

U.S. response to attack

U.S. Central Command in Doha, Qatar, confirmed the suicide bombing but had no additional details. Maj. Gen. Victor Renuart said the attack was "a symbol of an organization that's starting to get a little bit desperate," but added it would have no "operational impact" on U.S. forces.

"There is a fair amount of civilian traffic that we have to be very cautious with. And obviously in this case these forces took advantage of a situation," Renuart continued.

Palestinian militant group announces involvement

Meanwhile, the Palestinian militant group Islamic Jihad announced Sunday that it has sent suicide bombers to Iraq to help defend Baghdad.

"Al-Quds Brigades [the military force of Islamic Jihad] brings to our people and nation the good news of the arrival of its first martyrdom to the heart of Baghdad," said a statement faxed to news organizations.

"This is to fulfill the holy duty of defending Arab and Muslim land," it said.

Islamic Jihad was formed in 1981 to fight against and destroy the nation of Israel.

In the past 30 months of fighting with Israel, militant groups have sent dozens of young men and a few women into Israeli cities, where they've killed hundreds with bombs and bullets.

suicide attacks - (n.) an attempt to kill or maim in which the person attacking kills him or herself in the process; this term has recently been applied to Palestinian militants who attach explosives to their bodies before entering areas in which to detonate the explosives, often killing civilians and/or military targets

posthumous - (adj.) following or occurring after death (Merriam-Webster)

Palestinian - (n.) a person from Palestine.
Palestine - 1: ancient region SW Asia bordering on E coast of the Mediterranean & extending E of Jordan River 2: former country bordering on the Mediterranean on W & Dead Sea on E; a part of the Ottoman Empire 1516-1917, a British mandate 1923-48; now a national identity co-existing with Israel. Arab Palestinians in the West Bank have had limited self-rule since 1993. (Merriam-Webster)

martyr - (n.) a person who sacrifices something of great value and especially life itself for the sake of principle (Merriam-Webster)

Arabs - (n.) a group of people originally inhabiting Arabia who spread throughout the Middle East, N Africa, and Spain during the seventh and eighth centuries. Sometimes defined as a person who speaks Arabic.

Muslim - (n.) a follower of Islam, a religion originated in the 6th century and based on the teachings of Muhammed who is believed to be a prophet of God; the literal meaning of Muslim is "one who surrenders (to God)" and the beliefs of Islam are found in the Holy Qur'an