BAGHDAD (Reuters) - A female suicide bomber wearing an explosive vest struck a checkpoint of neighborhood patrol volunteers in Baquba, capital of Iraq's restive Diyala province, killing 10 people and wounding eight on Wednesday, police said.

It was the latest in a wave of suicide bomb attacks that has appeared to intensify in recent days and weeks, even as overall levels of violence in Iraq have fallen.

Two policemen and four patrol volunteers were among the dead, police said. Among those killed was Abdul-Rafaa al-Nidawi, whom police described as the coordinator between U.S. forces and the volunteer patrols in the city.

The mainly Sunni Arab neighborhood patrols, paid by U.S. forces to oppose Sunni al Qaeda militants, have frequently been targeted by suicide bombers in recent months.

Al Qaeda leader Osama bin Laden, who is not believed to have direct control over the Iraqi militants that use his organization's name, threatened attacks against the patrol members in an audio tape released last week.

Strikes by female suicide bombers are comparatively rare but there have been several in recent weeks in Diyala, including one which killed 16 people on December 7 and another which wounded seven people at a police station in Baquba on New Year's Eve.

Overall violence in Iraq declined dramatically over the second half of 2007. But U.S. military figures released over the weekend show suicide bombings increased after falling to a low in October.

The past week has seen major suicide bomb attacks most days.

A bomber in a suicide vest killed 30 mourners at a Baghdad funeral on New Year's Day, the deadliest strike in the capital for months. On New Year's Eve a suicide car bomb killed 11 people including five children in a town north of Baghdad.

On Christmas day two separate strikes on neighborhood patrol volunteers killed at least 33 people.

U.S. forces say they have driven al Qaeda Sunni Arab militants out of most of the territory they once controlled, but the militants still retain the capability to stage so-called "spectacular" strikes aimed at killing large numbers of people.

Al Qaeda has frequently targeted the neighborhood patrols, which were initially set up by tribes that turned against the Sunni Islamist group and are now springing up throughout Sunni Arab areas with U.S. funding and support.

(Writing by Peter Graff; editing by Ross Colvin)