Chlorine Attack Kills 20 in Iraqi Town

BAGHDAD, April 6 — Twenty people were killed and 30 wounded in Ramadi today when a suicide bomber drove a truck loaded with explosives and chlorine gas toward a residential complex, police said. Another 50 had trouble breathing after the attack.

The truck was headed toward a police checkpoint, but when policemen opened fire, the bomber veered toward the residential complex nearby and detonated the explosives, police said. Women and children were among those killed and wounded.

It was the sixth chlorine bomb detonated in the Anbar province in the last two months and the most lethal, though it is unclear if the victims were killed by the explosion or the chlorine. The Anbar province is a stronghold of the Sunni insurgency, and a haven for al-Qaeda.

There has been fierce fighting in the area between tribes that support Al Qaeda in Mesopotamia and those who oppose it and are beginning to work more closely with the government. In the past two months, there have been assassinations and bomb attacks on the tribes opposing Al Qaeda.

In the southern province of Diwaniya today, American and Iraqi forces raided several residential neighborhoods and engaged in gun battles with Mahdi Army fighters loyal to anti-American cleric Moktada al-Sadr. Three Mahdi Army fighters were killed and four wounded in a push to curb the group’s increased influence in the area.

The American and Iraqi forces began the raid by distributing pamphlets urging people to cooperate with security forces. Then American helicopters fired missiles that wounded 15 civilians.

American forces later fired on a Toyota sedan, killing all three passengers inside. And two students were killed by mortar when Americans fired on a college residence by mistake, Iraqi police said.

Three American vehicles were destroyed.

The raid angered representatives of Mr. al-Sadr’s movement. “This operation is unjustified and will stir up the situation in the time where a peace conference was supposed to be held between the Sadrists and the security forces,” said Haydar Al Natiq, of the Sadr office in Diwaniya.