BAGHDAD - A U.S. Army general on Sunday warned that American casualties would rise in the coming months, a prediction underscored by the deaths of six soldiers and a foreign journalist in a roadside bombing north of Baghdad. Five other American troops died elsewhere over the weekend.

Maj. Gen. Rick Lynch, commander of the 3rd Infantry Division, said casualties would climb as American troops went deeper into enemy territory as part of a stepped-up military operation ordered by President Bush in January. Lynch, who oversees a swath of territory to the south and east of Baghdad, gave his bleak prediction on the heels of the deadliest month so far this year for American forces in Iraq.

In April, 104 U.S. troops were killed, only the fourth time since the beginning of 2005 that U.S. deaths have exceeded 100 in a single month. At least 25 troops have been killed so far in May, a grim start to a month in which Democrats are expected to keep up pressure on the White House to plan a withdrawal from Iraq.

At least 3,376 American troops have been killed since the U.S.-led invasion in March 2003, according to the website icasualties.org, which tallies casualties.

The latest American deaths came on a bloody day for Iraqi security forces and civilians as well. At least 58 Iraqis died in a string of attacks, including 42 killed when a car bomb tore through a market in the Baghdad neighborhood of Bayaa.

North of the capital, in Samarra, 12 police officers died when a suicide bomber rammed a car into the police headquarters.

Witnesses said scores of vehicles filled with people waving black flags representing the Islamic State of Iraq, an Al Qaeda-linked Sunni Arab insurgent group, cruised menacingly through the city before the attack. The occupants fired on police stations, killing one officer before the car bomber struck.

Samarra's police chief, Col. Jaleel Nahi Hassoun, was killed in the blast.

In February 2006, Sunni insurgents destroyed Samarra's Golden Mosque, one of Shiite Islam's most important shrines, in an attack that unleashed fierce sectarian warfare.

Bleak assessment

In his comments, Lynch echoed previous warnings that insurgent groups linked to Al Qaeda were escalating attacks in hopes of fueling sectarian violence.

Al Qaeda is "out there looking for another Golden Mosque," Lynch said.

He gave a bleak assessment of the situation on the ground. In coming months, as the remainder of 28,500 additional U.S. troops move into place to enforce the security plan launched Feb. 13 at Bush's command, Lynch said, American casualties will go up.

"There are going to be increased casualties during this surge because we're taking the fight to the enemy," Lynch told journalists.

He said troops in his area of operation were facing a "thinking enemy" that had been on the ground far longer than most U.S. soldiers and had adapted techniques such as planting roadside explosives deeper to thwart high-tech equipment.

"He dominates that terrain," Lynch said, adding that 13 of his troops had been killed since coming to Iraq in March. His region includes the provinces of Najaf, Karbala and Babil and soon will expand to Wasit, which stretches to the Iranian border. Lynch said most of his troops had died as a result of armor-piercing roadside bombs that U.S. officials allege are coming from Iran.

Lynch repeated U.S. assertions that agents from Shiite-ruled Iran were providing weapons to both Sunni and Shiite insurgents to add to the chaos. He said evidence in his area indicated "Iranian influence" on both sides of the sectarian divide, in terms of weaponry, training and technology. He would not go into detail.

"I think it's naive to think they aren't reaching out to the Sunni extremists as well," Lynch said of the Iranians.

Iran has denied involvement in Iraq's unrest.

Lynch praised the progress of Iraqi security forces being trained to take over from U.S. and other foreign troops, but said the forces - particularly the Iraqi police - needed more time.

"If we walk away ... before the Iraqi security forces are ready to stand up and maintain that security, it's going to be a mess. And that indeed is going to take some time," he said.

The latest attacks underscored the challenges troops face.

Eight U.S. troops died in combat Sunday, including the six killed in Diyala province, a Sunni stronghold east of Baghdad, when a roadside bomb exploded under their vehicle. A journalist traveling with them also was killed, the military said in a brief statement. It did not identify the journalist, but a military spokesman, Lt. Col. Chris Garver, said later the victim was on a temporary assignment to Iraq and was neither American nor Iraqi.

There has been an increase in U.S. troop deaths in Diyala since the start of the security plan, which drove many insurgents out of Baghdad and Al Anbar province to the west. At least 60 American soldiers have been killed in the province so far this year, compared with 20 all of last year.

Two other soldiers were killed Sunday in separate roadside bombings, one in north Baghdad and one in the southern part of the city. One more soldier died of noncombat-related injuries.

The military announced the deaths of two Marines in Al Anbar province, west of Baghdad, on Saturday.

Civilian toll

There also were signs of a resurgence in sectarian death squad killings, which had appeared to drop significantly since the security plan's launch. Police in Baghdad on Sunday reported finding at least 25 bodies across the capital in the previous 24 hours. It was the fourth time in the last week at least 25 bodies were found in a day. In the preceding four weeks, the daily toll reached 25 only twice.

Violence hit hard Sunday at civilians across Iraq, with the worst attack taking place at a popular outdoor market in Bayaa, in south Baghdad. Police said scores of people were injured in addition to the 42 killed when a car bomb went off in the late morning.

Other victims of violence included an assistant college dean gunned down in the Sunni neighborhood of Adhamiya in north Baghdad and a civilian killed in a roadside bombing in Dora, another notorious Sunni area of south Baghdad.

The U.S. military also reported Sunday that it had found a torture room and more than 150 mortar rounds, ammunition and bomb-making equipment in an early morning raid in the Baghdad neighborhood of Sadr City, a Shiite stronghold.

"They found a room that clearly had bloodstains in it. It had handcuffs in it," said Army Maj. Gen. William B. Caldwell IV, a military spokesman. Caldwell said the raid was part of an attempt to arrest a "known terrorist" linked to Shiite extremist groups.

The amount of munitions in the house was so large that U.S. troops decided to detonate them inside the building after clearing people out of nearby dwellings, Caldwell said.

Residents said at least two civilians were killed when U.S. helicopters bombed houses in the area.

Caldwell said troops came under grenade and gun fire while conducting the raid, which lasted from about 1:30 a.m. to 6 a.m. The suspect was not captured, but a separate military statement said eight to 10 "armed individuals" were killed in battles with U.S. forces

susman@latimes.com

Special correspondent Hameed Rasheed in Samarra and correspondents in Baghdad and Hillah contributed to this report.

Copyright 2007 Los Angeles Times