An explosion, apparently caused by a suicide bomber, ripped through a mosque in an eastern Pakistani city during Friday prayers, killing at least 14 people and injuring dozens of others, officials said. Police said that more than 100 people _ and possibly as many as 500 _ were inside the mosque in the center of Sialkot city at the time of the blast, which triggered a riot by outraged worshippers. Interior Minister Aftab Khan Sherpao said 14 people were killed and dozens were injured, but said he had no information about what caused the explosion.