Militants in Iraq have stormed a university campus in the western city of Ramadi, taking dozens of students and staff hostage.

One student at the Anbar University campus said "everybody is in panic".

One report said some guards had died and that the militants were from the Islamic State in Iraq and the Levant.

The western province of Anbar is a focal point of Iraq's rising sectarian violence, with a number of areas controlled by Sunni militants.

The areas include parts of Ramadi, where the militants have been battling security forces of the Shia-led government for months.

Sealed off

Police said militants had infiltrated the campus from the neighbouring al-Tasha district, blowing up a bridge that connects to the university's main gate.

Security forces have sealed off the campus and one Agence France-Presse reporter said an assault led by special forces was under way.

The staff and students were reportedly being held in a dormitory.

One student in the building, Ahmed al-Mehamdi, spoke to the Associated Press news agency by telephone.

He said he awoke to gunfire and saw armed men running across the campus. The gunmen entered the dormitory and told everybody to stay in their rooms.

He said: "The gunmen took some students to other university buildings. For the rest of us, we are still trapped in our rooms and everybody is in panic, especially the Shia students."

The violence in Anbar meant there was no voting there in the 30 April parliamentary elections.

Prime Minister Nouri Maliki's Shia-led alliance won the elections, but fell short of a majority.

Mr Maliki wants a third term, but other parties have voiced strong opposition.

They blame him for the sectarian violence, which has left more than 3,500 people dead this year, and accuse him of trying to monopolise power.

He blames external factors like the conflict in Syria for exacerbating the violence, and his opponents for the current political stalemate.

The Islamic State in Iraq and the Levant has carried out dozens of deadly attacks both in Iraq and Syria and imposes strict Islamic rule in the areas it controls.

On Thursday, scores of unidentified militants stormed checkpoints in the central Iraqi city of Samarra.

The advance was eventually halted when helicopter gunships and military reinforcements, including members of Iraq's elite counter-terrorism forces, were sent in.

The army said some 80 insurgents died.