Five police officers were killed and one was wounded on Sunday when a roadside bomb exploded in a volatile northeastern area of Iraq that is claimed by Arabs and Kurds, police said, Reuters reported.
The bomb targeted a patrol of police assigned to protect power installations near Khanaqin, 140 km (86 miles) northeast of Baghdad, in still-violent Diyala province, police said.
The all-out sectarian war triggered by the 2003 U.S. invasion has receded in Iraq over the past two years but attacks by suspected Sunni Islamist insurgents continue.
Iraqi and U.S. officials expect attacks to pick up ahead of a March 7 election, a critical juncture as Iraq stands on its own feet ahead of a U.S. withdrawal by end-2011 and signs deals with energy firms that could vault it into the oil big leagues.
Khanaqin near the Iranian border is one of many areas where Kurds based in their semi-autonomous northern enclave and the Arab-led government in Baghdad tussle for power.
Iraqi soldiers and Kurdish peshmerga fighters came close to blows in Khanaqin in 2008. U.S. officials fear that if not resolved, Kurd-Arab tensions could lead to Iraq's next major conflict.