65-year-old warshiper mohamed a hero to his community. >> translator: he acted immediately when the shooter entered the room, sat on top of him. after a while the board member came and helped holding him down. then police arrived and arrested the man. >> reporter: afterwards the suspect's home was searched by police. and another terrible discovery made. the body of a 17-year-old woman, the gunman's stepsister. police say the man is a suspect in her murder. the mosque shooting is being investigated as a possible act of terrorism after it emerged the gunman had expressed right wing sympathies online. on sunday mosque members were forced to celebrate the most important muslim holiday of the year at a local hotel. the country's prime minister visited the group.