Iraqi authorities have taken a brigade of up to 700 policemen out of service and put members under investigation for "possible complicity" with death squads following a mass kidnapping earlier this week, the U.S. military said Wednesday.

Meanwhile, a series of bombs went off in rapid succession in a shopping district in a mainly Christian neighborhood of Baghdad, killing 16 people and wounding 87, police said. The dead were among 26 people killed in attacks across Iraq.

The U.S. military also announced the death of two soldiers — the latest in what has been one of the bloodiest stretches of days for American troops this year. At least 17 troops have been killed in combat since Saturday, including eight U.S. soldiers who died in gunbattles and bomb blasts Monday in Baghdad — the most killed in a single day in the capital since July 2005.

A suicide bomber attacked an Iraqi police base in the town of Ramadi, an insurgent hotspot west of Baghdad, but guards shot at the explosives-packed vehicle, detonating it before it could hit the base, police said.

CountryWatch: Iraq

The Iraqi police officers were decommissioned following a kidnapping Sunday when gunmen stormed a frozen food plant in the Amil district, abducted 24 workers and shot two others. The bodies of seven of the workers were found hours later but the fate of the others remains unknown.

The action appeared aimed at signaling a new seriousness in tackling police collusion with militias at a time when the government is under increased pressure to put an end to the Shiite-Sunni violence that has killed thousands this year and threatened to tear Iraq apart.

Sunni leaders blamed Shiite militias for the kidnapping and suggested security forces had turned a blind eye to the attack.

The top U.S. military spokesman in Iraq, Maj. Gen. William B. Caldwell, said the Iraqi police brigade in the area had been ordered to stand down and was being retrained.

"There was some possible complicity in allowing death squad elements to move freely when they should have been impeding them," he told a Baghdad news conference. "The forces in the unit have not put their full allegiance to the government of Iraq and gave their allegiance to others," he said.

He said problems with the unit had emerged during a broad brigade-by-brigade assessment of police in Baghdad led by the U.S. military.

The suspended brigade has about 650-700 police, said Interior Ministry spokesman Lt. Col. Karim Mohammedawi.

The Iraqi Interior Ministry said Tuesday that the commander of the unit, a lieutenant colonel, had been detained for investigation and the major general who commands the battalion that includes the brigade had been suspended temporarily and ordered transferred.

Brig. Abdul-Karim Khalaf, the chief ministry spokesman, said a random selection of troops in the suspended unit were being investigated for ties to militias.

Sunni leaders have frequently charged that Shiite militiamen have infiltrated the Shiite-led police forces and have accused police of helping or allowing their attacks.

At the same time, U.S. and Iraq forces have been carrying out a district-by-district sweep in the capital since August. The military announced Wednesday that one soldier was killed a day earlier in a shooting in Baghdad, while a second died Tuesday from gunfire in the northern city of Kirkuk.

In Ramadi, a vehicle drove toward a checkpoint outside the base, located in a youth center near the Iraqi army headquarters in the city. Guards opened fire on it and it crashed into concrete blocks and exploded, a police official in the city said.

The attacker was killed but there were no other casualties, the official said, speaking on condition of anonymity because he was not authorized to talk to the press.

The U.S. military, which also has bases nearby, said the suicide attacker was driving a tanker truck, and that the blast lightly injured four policemen and damaged the Iraqi police base's gate.

Just before noon Wednesday, a car bomb and two roadside bombs blew up in the span of 10 minutes in a shopping district of the Camp Sara neighborhood, which is predominantly Christian, 1st Lt. Ali Abbas said.

The blasts left 16 dead and injured 87, including shoppers and 15 policemen. They destroyed cars and collapsed part of a nearby building, he said.

Bodies lay in the street next to burning cars. Rescue workers piled the corpses into an ambulance parked next to the crumbled facade of a building, while a policeman warned residents to evacuate because more bombs might explode.

An increasingly common insurgent tactic is to detonate one bomb to draw rescue workers and onlookers, then to explode a second device to cause more casualties.

One witness, who identified himself only by his first name, Hamdi, said a roadside bomb went off first and people started to gather, then the second blast went off.

"Then more people gathered and they were searching for their dead or missing relatives when the car bomb exploded," he told AP Television News. "Everybody knows this is a Christian neighborhood, they are neither Sunnis or Shiites, so why are they doing this?"

Earlier in the nearby New Baghdad area, a bomb hit a convoy carrying the Iraqi industry minister. Three police guards were killed and nine were wounded, but the minister was not harmed, Abbas said.

In Baqouba, 35 miles northeast of Baghdad, gunmen attacked a police patrol, killing two policemen and injuring eight people including six policemen, Diyala province police said.

Near Baqouba, Iraqi forces carried out a pre-dawn raid on homes in two villages, arresting 41 suspects and seizing weapons and ammunition, provincial police said. The province has been the scene of increasing violence in recent weeks.