Iraqi officials said a car bomb killed 10 people and gunmen executed eight more in Iraq's western Diyala province as U.S. Vice President Joe Biden was in Baghdad to mark the departure of U.S. troops.
The bomb exploded at a market in the mainly Shi'ite town of Khalis, 80 kilometers north of the capital, Baghdad. Authorities immediately imposed a curfew in the town.
In the Sunni town of Buhriz, some 30 kilometers from Khalis, gunmen stormed three houses and executed eight people. The houses belonged to former members of the Sahwa militia -- Sunni fighters who helped U.S. and Iraqi forces defeat Al-Qaeda.
Biden meanwhile attended a ceremony in Baghdad together with Iraqi Prime Minister Nuri al-Maliki.
The remaining 13,000 American troops are due to leave Iraq in the next few weeks, nearly nine years after the invasion that toppled Saddam Hussein.
compiled from agency reports