PESHAWAR, Pakistan - Two of the gunmen who stormed a university campus in northwestern Pakistan have been killed, police said, but other attackers are believed to be on the second and third floors of campus buildings and firing is still going on.

Deputy Inspector General Saeed Wazir said police believed that most of the students had been rescued but several gunmen remained at large inside the university.

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Mourners pay respect to Chinese student killed in US shooting

Grief along with calls for self-defense were expressed on Monday at a memorial service for 19-year-old Jiang Yue, a Chinese exchange student who was shot and killed in a road confrontation in Arizona over the weekend.

More than 200 people, including Jiang's fellow students, members of the Chinese community and local residents, gathered at the scene of the Jan 16 incident in Tempe.

Jiang, a native of Chongqing, was a sophomore finance major at the WP Carey School of Business at Arizona State University in Tempe.