A youth club in northern Iraq taken as the headquarters of the independent committee responsible for Iraq's landmark elections was attacked by mortars on Tuesday,police said.

The assault, which took place in Samarra, some 110 km north of Baghdad, was the latest in a spate of attacks devised to derail the US-sponsored political process highlighted by the upcoming elections.

"The mortar rounds hit the building taken by the Independent Electoral Commission as its headquarters in the city and caused great damage," a policeman who refused to give his name toldXinhua.

Nobody was hurt in the attack as it took place early in the morning, he added.

The Commission staff in Samarra, numbering at about 24, had resigned earlier this month in response to the call of the Muslim Scholars Association to boycott the elections.

An extremist group led by al-Qaida's ally Abu Mussab al-Zarqawi has threatened to strike the Iraqi security forces, which have been pinned hope on to protect voting centers.

Handouts attributed to "Tawhid wal Jihad (unity and holy war)"group were distributed in areas north of Tikrit, warning citizens against taking part in the elections, saying "anyone taking part would be eliminated during or even after the elections."

About 11 members of the Electoral Commission in the areasresigned because of the death threats.

With less than one week ahead of the polls due on Jan. 30,sabotages have spiralled in the vast Sunni populated area between Baghdad and Mosul.

Three polling centers in Tikrit, one center in Baiji and a fifth in Tuz were attacked by mortars on Monday night, without causing casualties.

Again, the attacks in Tikrit were later claimed by Zarqawi's "Tawhid wal Jihad".