A car bomb killed at least 10 people packed into a Baghdad market Wednesday, while an Iraqi government spokesman praised a decrease in attacks during a new security plan in the capital.

U.S. forces killed eight suspected militants in a raid north of the city, and captured six others in separate operations around Baghdad, the military said.

The car bomb hit at midmorning in Baiyaa, one of Baghdad's most popular shopping districts in a mixed Sunni-Shiite neighborhood. Hours after the blast, charred clothes hung from vendors' stalls. A woman in a long black veil dragged a shopping cart behind her, empty.

Black smoke rose from the smoldering wreckage of at least four cars gutted by the explosion, and damage reached the second story of buildings nearby. Corrugated tin roofs were peeled back by the force of the blast.

Shopowner Imad Jassim ran out into the street when he heard the explosion.

"People were in a state of panic. There was a lot of blood on the ground and we helped carrying the wounded to the ambulances," Jassim said.

"The terrorists behind this massacre want to paralyze life in Baghdad by attacking markets and public crowds," he said.

At nearby Yarmouk Hospital, some of the 20 wounded were wheeled outside on gurneys. The bodies of at least three women were shrouded by their black abayas, or traditional Islamic coverings.

Later Wednesday, police said guards outside the Bab al-Sheik police station in central Baghdad fired on a suicide truck bomber as he approached them. The bomber changed course and crashed into a cement barrier, detonating his explosives. Two civilians were killed and two policemen and another civilian were wounded in the blast and exchange of gunfire, police said.

The attacks came two weeks into a joint U.S.-Iraqi plan to halt burgeoning violence in Baghdad. Iraq's spokesman for the plan, Brig. Gen. Qassim al-Mousawi, praised a "remarkable decrease" in the level of violence in recent weeks.

"The level of terrorist attacks have sharply dropped," al-Mousawi said.

At least 70 militants have been killed and more than 450 arrested in Baghdad since the plan was announced Feb. 12, he said. More than 10,000 rounds of ammunition were confiscated in raids, al-Mousawi added.

U.S. troops conducted at least three raids in and around Baghdad early Wednesday, targeting Al Qaeda in Iraq and locals harboring the terror group, the military said.

U.S. intelligence reports indicated that militants linked to small arms fire and rocket attacks on U.S. forces were operating northeast of Taji, a town on the northern outskirts of Baghdad, the military said.

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Eight people died when American helicopters and fighter planes fired on a palm grove, and two suspects there were detained, it said. Four others were picked up in Baghdad.

Police said at least four roadside bombs exploded south of Baghdad on Wednesday, killing two people in separate blasts.

Two brothers of a leading Sunni lawmaker were gunned down in Muqdadiyah, a volatile city about 60 miles north of Baghdad, a relative said. The victims were the brothers of Salim Abdullah al-Jubouri, a representative of the Iraqi Islamic Party, which is part of the largest Sunni bloc in parliament, the Iraqi Accordance Front.

The party called the attack "cowardly" and a "desperate attempt to target moderate people."

In Mosul, 225 miles northwest of Baghdad, police said a high-ranking officer and his driver were killed in a drive-by shooting.

Col. Abdul-Hadi Mohammed Saleh was on his way to work when gunmen sprayed his car with machine gun fire, police said. Saleh's driver was killed and his bodyguard injured, they added.

The tortured body of another senior police officer was discovered in central Baghdad, about two months after the man disappeared, an Interior Ministry official said.

Six mortar shells landed on the Shiite Muslim village of al-Maail south of the Iraqi capital, killing one person and wounding 14, police said.

Security was stepped up Wednesday in Karbala, a Shiite holy city 50 miles south of Baghdad, ahead of a major Muslim holiday next month.

The city was being divided into nine security sectors with checkpoints separating them, said police chief Maj. Gen. Abu al-Walid.

Security teams would be deployed to search pilgrims streaming into the city to celebrate Arbaeen, a Shiite feast that marks the end of a 40-day mourning period after the anniversary of the death of Imam Hussein. He was the grandson of Islam's Prophet Muhammad and is buried in Karbala.

Cars, bicycles and carts would be banned from the city during the holiday period, al-Walid said.

Millions of pilgrims travel to Karbala each year to mark the holiday at the Imam Hussein shrine, and celebrations have been marred by increased violence in recent years.

Complete coverage is available in FOXNews.com's Iraq Center.