A 14-year-old student killed seven people, including his grandparents and five teachers, in shootings at his home and school in Nonthaburi, near Bangkok, before taking his own life. The attack, Thailand’s second school shooting this year, has renewed concern over gun control and the enforcement of existing firearms laws.

Twenty-three people were injured, with nine reported to be in critical condition. Police said the attack began shortly after 10:00 local time and appeared to have been carefully prepared; the gunman reportedly had more than 30 bullets remaining. No motive has been disclosed, and investigators are examining evidence from the home where he lived with his grandparents.