Police in southwestern Pakistan have detained 36 people, mostly Afghan refugees, for questioning about a suicide bombing inside a courtroom that killed a judge and 15 other people, an official said Sunday. The suicide bomber struck a crowded courtroom in the city of Quetta on Saturday in the deadliest of a series of attacks in recent weeks. There is suspicion in Pakistan that pro-Taliban militants are targeting sensitive sites to undermine the country's support of the United States, and an official in the region where Saturday's attack took place hinted at Afghan involvement. The explosion wounded 24 people and left bloodied clothes and body parts scattered next to wrecked furniture and shattered glass in the Quetta District Courts. It forced police - already on alert - to further tighten security nationwide.