A Thai teenager has killed at least five people and himself at a school outside Bangkok after shooting dead his grandparents, police say.Those killed at the school were all teachers and staff, while a further 23 people were injured in the incident on Friday, police said.The shooter, who was 14 years old, fired at least 26 bullets using a gun that had belonged to his grandfather, and 34 additional ammunition rounds were found by police.The motive was still being investigated, Education Minister Prasert Jantararuangtong told reporters.The shooting happened at the Debsirin Nonthaburi School in Nonthaburi province north-west of Bangkok."It's such a terrible incident Then it started again."In photos circulated by emergency workers, students streamed out of the Debsirin Nonthaburi School, on the north-western outskirts of Bangkok, as ambulances operated.The school had an enrolment of about 3,100 students and 147 teachers in the 2025 academic year, according to district authorities.The shooting on Friday is the second school shooting in Thailand this year after a teacher died and a student was injured in southern Thailand's Hat Yai district after a gunman opened fire at a school in February.Reuters/AP