Updated

A homicide car bomber struck a police checkpoint in a small town west of Baghdad on Monday, killing at least three people in the latest attack in a region that had once been a Sunni insurgent stronghold but later became key to a nationwide drop in violence.

It was the seventh bombing in two weeks in Anbar province, leaving a total of 24 people killed since July 20.

Persistent violence in Anbar and elsewhere in Iraq has heightened concern about the readiness of Iraqi forces to protect the people as U.S. troops begin pulling back.

American forces retain a presence in Anbar province, which was the birthplace of a Sunni revolt against Al Qaeda in Iraq that has been pivotal to security gains over the past two years. But the Iraqis are the ones in charge of security.

Monday's bomber detonated his explosives at a police checkpoint in Saqlawiyah, a small highway town 45 miles (75 kilometers) west of Baghdad. A police official in nearby Fallujah said four civilians and three policemen also were wounded.

The official spoke on condition of anonymity because he was not authorized to release the information.

The attack occurred a day after a parked car bomb killed five people and wounded more than 30 in Haditha, a Euphrates side city farther west in Anbar province.

Five other bombings have been reported in Anbar since July 20, when a car bomb exploded near the provincial governor's office, killing two policemen.

A homicide car bomber wounded 20 people at a restaurant in the provincial capital of Ramadi on July 21, a double car bombing killed four people in Fallujah on July 25, a homicide bomber killed five people in a funeral tent near Ramadi on July 26 and a homicide truck bomber killed five civilians in the Syrian border town of Qaim on July 30.

The surge in violence in an area that has been seen as one of the war's success stories comes as the U.S. military has warned it expects insurgents to continue bombings in a bid to reverse a drastic drop in violence over the past two years. But commanders say overall attack levels remain low.

Roadside bombs on Monday also killed two Iraqi soldiers and wounded four others in separate attacks in the volatile city of Mosul in northern Iraq, according to police.

Meanwhile, Iraqi Prime Minister Nouri al-Maliki, a Shiite, pledged solidarity with Kurds during a visit to Halabja, a Kurdish city that was devastated by a 1988 chemical attack ordered by Saddam Hussein.

"We were all victims of the defunct regime, we all paid the price, and what unifies us is that we paid the price together," he said. "And it is the right of our people to live in peace and harmony and with equality."

The remarks came a day after al-Maliki joined Kurdish leader Massoud Barzani in promising to work together to defuse rising tensions and address a range of disputes over oil and land that have poisoned relations and threatened to become a new source of conflict for the battered country.

The northern, self-ruled Kurdish region has enjoyed relative calm since the 2003 U.S. invasion that ousted Saddam, but U.S. officials have warned that Arab-Kurdish tensions could jeopardize security gains elsewhere and urged the rival factions to overcome their differences.