HAWIJA, Iraq - Faced with attacks against their sheikhs and clan members, a number of Sunni tribes from Hawija – an insurgent bastion in northern Iraq - have declared war on Al-Qaeda's frontman in Iraq, Abu Musab al-Zarqawi.

"We shall fight all those who commit such attacks, notably Al-Qaeda," the tribal leaders said in a statement that has been circulating around Hawija.

In the last month-and-a-half, the head of Al-Nuaim tribe, Ibrahim Al-Nuaimi, and one of the heads of the powerful Jubur tribe, Ahmad Mehdi Saleh, have been assassinated in this Sunni rebel bastion, 220 kilometers (137 miles) north of Baghdad.

Khaled Abdel Hussein, a doctor at Hawija's general hospital, was also killed by armed men who barged into the hospital building and sprayed it with bullets.

General Hatem Khalaf Al-Obaidi, head of the police of nearby Kirkuk, was also gunned down while in the area.

"It is a terror campaign against our leaders," Sheikh Abdel Rahman al-Assai, head of the Obaidi tribe, said.

"We are not going allow them to silence us and do this to us. The resistance opposes the occupation and is an Iraqi affair.

"Terrorists and Takfiris (Sunni extremists) kill, kidnap and terrorise our people. We cannot accept this," he said.

He felt it was legitimate to kill these men as they belong to "Zarqawi and such groups."

Insurgent activity is rife in the area which has earned the nickname of Iraq's Kandahar - an allusion to the former Taliban stronghold in Afghanistan.

On February 22, four US soldiers were killed there when their convoy was hit by a roadside bomb.

The tribal leaders said groups linked to Zarqawi were carrying out attacks on the "army, police, oil and gas pipelines and technicians which harms the interests of Iraq."

"We never offered refuge to terrorists. All those who offer shelter to terrorists will be treated like terrorists," their statement added.

"We reject violence and the murders of civilians in the Arab areas."

"These dark forces strike all religious people and their symbols," a local Hawija council member Hussein Ali al-Jubur said.

Attacks on Iraqi security forces also delays the withdrawal of foreign coalition troops, he noted.

"We are against any action causing losses to our security forces as it weakens them and delays the withdrawal of the occupying forces (coalition forces)," he said.

"Attacks by Zarqawi or others worsen the sorrows of our people, deprive them of electricity, water and fuel," he added.

The call to arms by the tribes was welcomed by General Anwar Hama Rahma, head of the Iraqi military in Kirkuk who offered his full support to their fight against Al-Qaeda insurgents.

The new stand by Sunnis around Hawija mirrors that to the south in Samarra, where the killing of a key tribal sheikh last October had strained ties between Qaeda fighters and locals, although the sides have since reportedly brokered a truce.

The US military has also reported clashes between nationalist insurgents and Al-Qaeda in Al-Anbar province, considered a bastion of rebel violence.