Two U.S. service members were killed in Iraq Sunday, making June the deadliest month for American combat fatalities there in more than two years.

The U.S. military announced the deaths, saying the two were killed in northern Iraq while conducting operations. No further details were immediately available.

So far this month, 11 U.S. troops have died in combat-related situations in Iraq, the highest monthly total for such deaths since May 2009 when American forces were still operating in Iraqi cities.

Nearly 50,000 American troops are still in Iraq, but an agreement between Washington and Baghdad stipulates they withdraw from the country entirely by the end of 2011.

Also Sunday, Iraqi officials said a suicide bomber in a wheelchair attacked a police station near Baghdad, killing at least two people and wounding 18 others.

Authorities say the bomber blew himself up at the entrance to the police compound in the central town of Tarmiyah. At least nine of those wounded were policemen.

Elsewhere, police say a bomb went off Sunday near a car carrying the mayor of the northern Iraqi town of Riyadh in Kirkuk Province. Two people were wounded, but the mayor was unharmed.

Iraqi security personnel and officials have become a frequent target of insurgents as the Iraqi government prepares for the withdrawal of U.S. forces.

In another development, an Iraqi official said Sunday a court has sentenced the wife of a slain al-Qaida leader to life in prison on charges of providing assistance to terrorists. A judicial council spokesman says the court handed the life term to Hasna Ali Yahya on Thursday.

Yahya, a Yemeni national, was married to Abu Ayyub al-Masri, the leader of al-Qaida's Iraqi affiliate until Iraqi and U.S. forces killed him and another top militant in a security operation in April 2010. Such operations have weakened al-Qaida in Iraq in recent years, but the group has continued to stage deadly attacks across the country.