Fallujah, Iraq ? A car bomb exploded Tuesday near a police station on a major street in the tense city of Fallujah, killing at least four people, police said. The attack came a day after a series of suicide bombings in Baghdad left about three dozen dead.

With Baghdad residents still in shock from the string of bombings the day before, strong explosions were heard after sunset Tuesday. At least three mortars exploded in the Jadriya district, across the Tigris River from the palace headquarters of the U.S.-led coalition, Iraqi police said.

There was no immediate word on casualties or damage.

In Washington, President Bush blamed both loyalists to Saddam Hussein and foreign terrorists for the recent attacks.

“Basically what they’re trying to do is cause people to run,” Bush told a Rose Garden news conference Tuesday. “That’s what terrorists do.”

Aid organizations were weighing whether to pull personnel out of Iraq after two days of dramatic attacks in Baghdad. Monday was the bloodiest day in Baghdad since Saddam’s regime fell more than six months ago. Suicide bombers struck the Red Cross headquarters and three police stations, killing eight Iraqi policemen, at least 26 Iraqi civilians and an American soldier.

Also Monday, another U.S. soldier was killed when insurgents fired a rocket-propelled grenade attack at munitions clearers, the military said. Six Americans were wounded.

Insurgents on Sunday hammered a downtown hotel with rockets, killing an American soldier. The same day, one of Baghdad’s three deputy mayors — Faris Abdul Razzaq al-Assam — was assassinated in a drive-by shooting, the U.S. military announced.

Investigators are trying to determine whether a would-be fifth suicide bomber from Monday’s attacks — who was caught before he could detonate his explosives — is truly Syrian as he claims, an official of the U.S. occupation said.

U.S. Army 4th Infantry Division soldiers gather outside a first aid station in Tikrit, Iraq. One U.S. soldier was wounded when insurgents opened fire late Tuesday on the southern gate of the main U.S. military base in Saddam Hussein's hometown.

The man had a Syrian passport and investigators are trying to determine if it’s authentic, said the official on condition of anonymity.

In the northern city of Mosul, the editor of an independent Iraqi newspaper was shot and killed Tuesday by men who followed him up to the roof of his office as he made a call.

Ahmed Shawkat, editor of the independent “Without Direction,” had received death threats for his writings, which have been critical of the anti-U.S. resistance as well as the U.S. occupation, said his daughter, Roaa.

Explosions persist

Tuesday’s bomb in Fallujah, 40 miles west of Baghdad, was in a Toyota that exploded in front of a power station and about 30 yards from a school and 100 yards from a police station, witness Hamid Ali said. The target was unclear.

Hours later, after sundown, eight massive explosions were heard in the city, but their cause was not known.

A U.S. Army soldier, of Charlie company, 1-22 Infantry regiment, 4th Infantry Division, holds an unidentified Iraqi man by the head in Tikrit, Iraq. The man had been warned to stop driving a motorcycle, and troops took it Tuesday.

Tawfiq Mijbel, who was badly injured by shrapnel in the morning blast, said he had been driving directly behind the vehicle that exploded. “It stopped in front of the power company. A man got out, while another stayed in the car. A few seconds later it blew up,” Mijbel said from his hospital bed.

Khamis Mijbal, who owns a shop opposite the spot where the car blew up said the blast produced a ball of fire and that debris flew everywhere.

The school was closed, but police said one body was found inside. Police Col. Jalal Sabri said all the victims appeared to have been bystanders.

Troops attacked

Tuesday night, insurgents opened fire on the southern gate of the main U.S. military base in Tikrit, Saddam’s hometown, wounding at least one soldier from the 4th Infantry Division, witnesses said.

The night before in Mosul, Iraq’s third-largest city, two U.S. patrols were ambushed, wounding three American soldiers.

In southern Iraq, an explosive went off as a patrol passed, wounding a British soldier and two Iraqis, the military command said.