ISLAMABAD , Pakistan ( CNN ) -- Back-to-back suicide bombings killed at least five people at a university here Tuesday and wounded nearly two dozen , authorities said . Police investigators collect evidence at the suicide blast site at Islamic International University in Islamabad . The explosions occurred at the International Islamic University in the Pakistani capital , said police official Bin Yamin . Naeem Iqbal , Islamabad police spokesman , said three men and two female students were killed , and 22 people were injured . At least four of the injured were in critical condition , said Altaf Hussein , a doctor at a hospital . All the victims are between the ages of 18 and 25 . Usman Virk , a student , said he heard one explosion in the men 's section of the university , followed by a blast in the cafeteria in the women 's section of the university . Watch more about the attacks » . Virk said he saw several injured students with blood-soaked clothes being taken away by rescue crews . More than 12,000 foreign and local students , including 5,500 women , are enrolled in the 29-year-old university . The university Web site describes the school as a `` unique center of learning in the Muslim world which strives to combine the essentials of the Islamic faith with the best of modern knowledge . '' In recent weeks , Pakistan has been relentlessly rocked by a wave of suicide attacks as Islamic militants retaliate against a military offensive to rout insurgents operating along the Pakistan-Afghan border . On Friday , a suicide car bomber detonated near a police station in Peshawar , the capital of the North West Frontier Province . The blast killed at least 13 people , most of them civilians . A day earlier , militants attacked two police training centers and the country 's Federal Investigation Agency in Lahore in eastern Pakistan . At least 30 Pakistani police officers and civilians were killed in those attacks . At least 10 attackers also died . And on October 10 , militants held dozens of hostages for 22 hours inside an army headquarters in Rawalpindi , which neighbors Islamabad . Eleven military personnel , three civilians , and nine militants were killed in the siege . CNN 's Reza Sayah contributed to this report .
All the victims of the attack are between the ages of 18 and 25 . Took place outside International Islamic University in Islamabad . More than 12,000 foreign and local students are enrolled at university . Score: 6