A teenage student opened fire at a school in Thailand's Nonthaburi province, killing several people including his grandparents before dying by suicide, according to police. The shooting occurred Friday at a high school in the Bang Kruai district. The suspect, a ninth-grade student, used a 9mm handgun that belonged to his grandfather, who was a teacher, police said. Casualty figures vary: The Guardian reports at least seven people dead and 15 injured, with the suspect also dead. NDTV reports a teacher dead, four injured, and the student dead. Both accounts agree the suspect killed his grandparents before the attack. The motive remains unclear. Natthaphong Ruengpanyawut, leader of the People's Party, called the shooting "another wake-up call to Thai society." An investigation is under way.