Jihadist gunmen wearing suicide vests stormed a police station in the Iraqi city of Samarra Monday, sparking clashes with the security forces, officials said.

"There was a terror attack on Mutawakil police station, now the Iraqi forces are besieging them," interior ministry spokesman Saad Maan told reporters.

The Islamic State group claimed responsibility for the attack in central Samarra, a city 110 kilometres (70 miles) north of Baghdad, via its propaganda agency Amaq.

Maan said the attackers holed up inside the police station were exchanging fire with the security forces besieging them.

A police major from Salaheddin province where Samarra is located said five attackers had already been killed and added that reinforcements had been deployed.

Samarra is home to a major Iraqi security headquarters and to an important Shiite shrine where a 2006 bombing touched off two years of sectarian bloodletting.

IS in Iraq is mostly focused on defending its last major urban stronghold of Mosul, but has launched a number of diversionary attacks elsewhere in the country since the start on October 17 of a broad offensive by the security forces to retake the northern city.

IS claimed a similar attack in Samarra on November 28 in which five gunmen wearing suicide vests killed at least four member of the security forces after infiltrating the city.

Iraqi security officials did not immediately release information on any casualties of Monday's attack among police ranks.

History of deadly attacks in Iraq
Baghdad (AFP) Jan 2, 2017 - The Islamic State group has claimed responsibility for a series of deadly attacks in Iraq since mid-October including three since New Year's Eve.

The latest on Monday saw at least 32 people killed in a suicide car bombing that targeted a Shiite neighbourhood of the capital Baghdad.

At least 27 people were also killed by twin explosions in a busy market area in central Baghdad on New Year's Eve, while another seven died on Sunday in an attack south of the Shiite shrine city of Najaf.

They were the latest in a spate of attacks since the army launched an offensive in mid-October to recapture Mosul, the country's second city and last remaining IS stronghold in Iraq. One on November 25 saw 70 people, mostly Shiite pilgrims, killed south of Baghdad.

The wave of violence has shocked many, but the attacks are still far from the deadliest since the US-led invasion of Iraq in 2003:

- July 3, 2016: 323 people are killed when a suicide truck bomber attacks a shopping area in the Baghdad district of Karrada.

- October 25, 2009: 153 people are killed and more than 500 wounded when two car bombs explode in Baghdad.

- August 14, 2007: More than 400 people are slaughtered when four suicide truck bombs target members of the ancient Yazidi religious sect in two Kurdish villages in northern Iraq.

- July 7, 2007: At least 140 people are killed in a suicide truck bombing in Amerli village in northern Iraq.

- April 18, 2007: A wave of car bomb attacks on Shiite districts of Baghdad leaves 190 dead.

- March 27, 2007: An anti-Shiite attack in the northern town of Tal Afar kills 152.

- February 3, 2007: A suicide truck bomb attack in a Baghdad market kills at least 130.

- November 23, 2006: At least 202 die in a string of car bombings in Baghdad's Sadr City.

- September 14, 2005: At least 128 people are killed in a series of suicide bombings in Shiite districts of Baghdad.

- March 2, 2004: Bomb attacks on Shiites in the holy city of Karbala and in Baghdad kill more than 170.