The bombing Friday of an Iraqi mosque — the third such attack this month — illustrates the "desperation of the enemies of the Iraqi people" but will not deter American forces, President Bush said.
The car bombing at the Imam Ali mosque killed 75 people, including Ayatollah Mohammed Baqir al-Hakim (search), one of Iraq's most important Shiite clerics.
"His murder today, along with the murder of many innocent men and women gathered for prayer, demonstrates the cruelty and desperation of the enemies of the Iraqi people," Bush said in a statement released Friday in Crawford, Texas, where he is ending his monthlong stay on his ranch.
"The forces of terror must and will be defeated. The united efforts of Iraqis and the international community will succeed in achieving peace and freedom."
Secretary of State Colin Powell called the bombing a "heinous crime against the Iraqi people and the international community."
Both he and Bush extended sympathies to the Iraqi people and Muslims of the Shiite sect around the world.
"This attack underscores once again that we are all victims of terrorism, and that no political cause can justify the taking of innocent life," Powell said in a statement. "The coalition and the international community will continue to work closely with the Iraqi people to build a better future for Iraq."
Officials at the Pentagon said the incident was viewed as a tragedy, the latest example of the difficulties in trying to bring stability to Iraq, but not unexpected.
Military officials have been saying for weeks that attacks — most believed launched by loyalists of fallen president Saddam Hussein — have grown increasingly sophisticated over the weeks.
Elsewhere, a senior administration official called the bombing a horrible incident and said it really was an attack on the Iraqi people.
The United States has offered to assist the Iraqi Interior Ministry in its investigation, said the official, speaking on condition of anonymity.
A car bombing at the Jordanian Embassy in Baghdad killed 17 early in August and one at the United Nations headquarters killed 23 last week before today's bombing claimed at least 75 lives.
Defense officials also noted that attackers took advantage of scant security at the U.N. and mosque.
No coalition troops were near the mosque out of respect for the holy site, said Pentagon spokesman Lt. Col. Jim Cassella. U.S.-led troops have been asked to stay away from the mosque by Shiite officials.
Likewise, U.N. officials had asked that there be no U.S. security at their headquarters to avoid linking themselves too closely to the occupation force, which has been the target of daily attacks.
FBI agents are helping investigate the two earlier bombings this month. But defense officials said the Iraqi police would lead the mosque bombing probe and U.S. investigators would assist only if asked.
It was unclear how many resources — and what expertise — the Iraqi force would have to investigate the attack since the force was just recently hired, trained and formed by occupation military forces.