Militants , including a female suicide bomber , attacked a university bus carrying women in southwestern Pakistan and then struck a hospital where the survivors were taken for treatment , authorities said Saturday . The militants laid siege to the Bolan medical complex in Quetta , holding hundreds of patients , physicians and nurses hostage as they battled security forces , authorities said . An intelligence official , who requested anonymity since he was not authorized to speak to media , told CNN a female suicide bomber carried out the bus attack . Twenty-eight people , including four militants , were killed in the siege at the hospital . The gunmen killed four security force members , a medical administrator , and the deputy commissioner of Quetta . Four nurses died in the crossfire , police said . Two militants blew themselves up , and two more died in a shootout , authorities said . Among the hospital patients were more than 20 people wounded in the university bus explosion , which killed at least 14 women , Interior Minister Chaudhry Nisar Ali Khan said . Several others were wounded in another blast tphat struck near the hospital 's emergency room as the bus bombing victims were rushed in . `` All the ( bus ) victims are women teachers and students , '' said Mir Zubair Mehmood , a police official in Quetta . The blast shattered the windows of offices and classrooms inside Sardar Bahadur Khan Women University . The university bus was parked at the school on the outskirts of Quetta , the capital of Balochistan province in southwestern Pakistan . There was no immediate claim of responsibility . But Pervez Rasheed , the country 's information minister , said , `` We do not think there is any foreign involvement in these attacks -- this looks like homegrown terrorists . '' U.N. Secretary-General Ban Ki-moon condemned the attacks , saying `` violence against women and educators has increased in recent years . The aim being to keep girls from attaining a basic right to education . '' Ban called on Pakistan 's new leader , Nawaz Sharif , to do `` all possible to bring the perpetrators to justice . '' On Sunday , gunmen killed two polio workers who were making home visits in Khyber Pakhtunkhwa province in northwestern Pakistan , police said . Sharif called the attack `` cowardly and inhumane . '' Earlier Saturday , assailants bombed the home of Pakistani founding father Muhammad Ali Jinnah in Balochistan , killing a police officer and wounding an employee , authorities said . The attack occurred in Ziarat , one of the country 's top tourist spots , about 150 kilometers ( 93 miles ) from Quetta . Jinnah spent the last days of his life at the home . Islamabad summons a top U.S. envoy over deadly zone strike .
Polio workers shot dead on Sunday in northwest Pakistan . Female suicide bomber attacks bus with women on it , source tells CNN . Pakistani official thinks `` homegrown terrorists '' may be responsible . Officer dies in bombing of Pakistan founder 's home .