Taliban gunmen stormed a university in Northwestern Pakistan triggering a heavy gun battle with police and army.

FOX's Jessica Golloher has more from the Middle East Bureau on an attack which has killed at least 20 people:

The assault began shortly after the Bacha Khan University opened for classes.

Militants stormed the campus, triggering the hours-long gun battle after police and soldiers rushed to the scene. Several explosions were heard. The four attackers were eventually killed.

Pakistan's Prime Minister vowing to fight and destroy the Taliban and other militants, calling them a menace.

A spokesman for the Taliban faction in Pakistan calling the attack 'un-Islamic' and disowning the group responsible for it. Mohammad Khurasani denying the Taliban is responsible, saying the group considers students in the non-military institutions the future of the jihad movement.

In the Mid East Bureau, Jessica Golloher, FOX News.