Gunmen killed at least six Iraqi policemen and wounded 10 when they attacked their checkpoint north of Baghdad this morning.
Large numbers of insurgents armed with assault rifles and heavier weapons stormed the post in the town of Bores, near Baquba, 65 kilometres from the capital.
One policeman at the scene put the death toll as high as nine, with a further 12 officers wounded.
The attack came at about 8am when many Shia Muslims were observing the start of the Eid al-Fitr holiday that marks the end of the holy fasting month of Ramadan. Most Sunni Muslims began the three-day holiday a day earlier.
The area of Diyala province is home to a mix of sectarian and ethnic groups; Sunni Arab insurgents have often attacked Shia civilians and a police force and army that they say is dominated by the Shia majority now in power in Baghdad.
A suicide bomber who gathered a crowd to buy dates from his truck killed at least 30 people on Saturday in the nearby Shia town of Howaider.