Islamabad , Pakistan ( CNN ) -- The death toll has risen to 33 in Friday 's twin blasts in Karachi , authorities said Saturday . One blast targeted a bus filled with Shiite religious observers , killing scores . Another explosion in front of a hospital where attack victims were being treated , a government official said . Along with the the deaths from both blasts , more than 160 people were injured , the government official said . Motorcycles were used in both assaults , police said , and they came during the Shiite observance of Arbaeen , which takes place 40 days after the anniversary of Iman Hussein 's death , also known as Ashura . Along with the fatalities , 69 people were injured in the first blast , said Dr. Saghir Ahmed , Sindh provincial health minister . The second blast happened in front of the emergency room at Jinnah Hospital , where doctors treated people from the first attack and others on stretchers were waiting to be taken to the crowded facility . Along with the 13 killed , 92 were injured . The last deadly blast in Karachi was in late December during Ashura , when more than 40 people were killed . -- CNN 's Nasir Habib contributed to this report .
The second explosion targeted Shiite religious observers on a bus . The first attack occurred outside a hospital treating victims of the first blast . Motorcycles were used in both attacks , say officials . A blast in Ashura in Friday , during Ashura , killed more than 40 people .