Terrorists exploded 13 car bombs across Iraq on Sunday, including eight in Baghdad within a three-hour span, but the New Year's Day onslaught killed no one and injured only 20 people, police said.

A Sudanese official, meanwhile, announced that six kidnapped employees were freed after Sudan announced it would close its Baghdad embassy as demanded by the kidnappers. A Cypriot man kidnapped four months ago also was freed after his family paid a ransom, a relative said.

The day's first car bomb in Baghdad exploded at about 8:15 a.m., wounding two Iraqi soldiers in an army patrol in a northern neighborhood, police Lt. Bilal Ali Majid said.

Seven more car bombs exploded over the next 2 1/2 hours, wounding a total of nine people, police said. One homicide attacker died. Police later detonated a ninth car bomb in a controlled explosion.

Near Tikrit, Saddam Hussein's hometown, a homicide bomber blew up his car near an American patrol, injuring six civilians, police 1st Lt. Ali Jasmin said. Iraqi police had no information on American casualties and U.S. officials had no immediate information.

A car bomb targeted a U.S. convoy in the northern city of Kirkuk, but caused no injuries, police Brig. Sarhat Qadir said. A second bomb was aimed at an Iraqi police convoy and wounded three civilians, Qadir said.

Another car bomb exploded near a U.S. patrol in Muqdadiyah, about 60 miles north of Baghdad, and Diyalaa police said there may have been Americans casualties. U.S. officials had no immediate comment.

On Saturday, at least 20 people were killed in a series of bombings and shootings.

U.S. Brig. Gen. Donald Alston said Sunday that officials had expected attacks to increase after the security measures put in place for the Dec. 15 parliamentary elections were relaxed.

"We're seeing that increase right now," he said. "This is perceived, inappropriately I would say, or inaccurately perhaps, by the enemy as a time of vulnerability as the government transitions ... to a permanent government."

In other violence, about a dozen gunmen attacked a police checkpoint in the northern city of Mosul, killing one bystander and injuring three policemen, police Brig. Saed Ahmed said.

Police killed two protesters in Kirkuk rioting over a countrywide gasoline shortage caused by deteriorating security for tanker-truck drivers, Capt. Ferhad Talabani said. He said the demonstrators set fire to a fuel station and attacked police.

The Palestinian Embassy in Baghdad announced that gunmen killed the son of an attache Saturday. Azzam Ibrahim Mohsin, 17, was inside a car house in western Baghdad when he was shot, Dalil al-Qusous, the Palestinian charge d'affairs told The Associated Press on Sunday.

The six kidnapped employees of Sudan's embassy were released Saturday, a Sudanese official said.

"We talked to the six of them by phone and they told us that they are now at the house of one of their friends," said the embassy's charge d'affairs, Mohamed Ahmed Khalil.

Al Qaeda in Iraq had set a Saturday deadline for Sudan to "announce clearly that it is cutting its relations" with the Iraqi government or it would kill the hostages. Sudan said Friday it would close its embassy in Baghdad.

Al Qaeda militants have kidnapped and killed a string of Arab diplomats and embassy employees in a campaign to scare Arab governments from setting up full diplomatic missions in Iraq.

In July, Al Qaeda abducted the top Egyptian envoy in Baghdad, Ihab al-Sherif, and two Algerian diplomats. It later announced they had been killed. The group also snatched two Moroccan embassy employees in June and said it sentenced them to death, though it never stated whether it carried out the sentences.

The released Cypriot was identified as Garabet Jekerjian, 41, who holds both Cypriot and Lebanese citizenship and was kidnapped by gunmen in Baghdad in August. His brother, Avo Jekerjian, told AP he was let go Saturday after a $200,000 ransom was paid to the kidnappers.

Jekerjian had worked for Geto Trading Ltd., a Cyprus-based company supplying food and alcoholic drinks to U.S. forces. Islam prohibits consumption of alcohol. His brother said the company contributed to the ransom, but he would not say how much.