At least 10 people were killed and over 30 others injured on Monday in a blast that hit a hospital in Pakistan's Quetta city following the killing of an advocate earlier in the day, police said.Former Balochistan Bar Association President Bilal Anwar Kasi was shot dead by unidentified gunmen in the provincial capital earlier on Monday, Dawn online reported.The explosion took place soon after lawyers arrived at the hospital when Kasi's body was brought in, police said.TV reports showed people trying to exit the hospital. Journalists present at the premises also came in the line of fire, Dawn online added.An emergency has been declared in hospitals across Quetta."This was a security lapse and I am having this personally investigated," Balochistan Home Minister Sarfaraz Bugti said.He said it was too early to determine the nature of the blast, and added that the hospital had not received any threats in the past, Dawn online added.