More than 50 people were killed in a series of suicide bombings as members of Iraq's security forces began voting in the country's first election since the withdrawal of U.S. troops in late 2011.

Attackers wearing police uniforms struck polling centers around Baghdad and north of the city, while roadside bombs targeted military and police convoys, leaving dozens injured.

In the deadliest attack, a suicide bomber detonated an explosive at a Kurdish political gathering in the town of Khanaqin, northeast of the capital, killing 30 people, and leaving more than 50 others wounded. The group was watching video of ailing Iraqi President Jalal Talabani cast his vote in Germany where he has been undergoing medical treatment.

No one has claimed responsibility for the attacks, but Sunni militant groups have previously targeted security forces and members of the nation's Shi'ite majority.

Early voting began Monday for those unable to cast their votes in Wednesday's parliamentary elections, including security forces, hospital and prison staff, as well as patients and inmates.

Analysts say voters will likely cast ballots along sectarian and ethnic lines with no single party expected to win a majority.