A 13-year-old student launched a knife attack at a primary school in Staškov, Slovakia, killing a 61-year-old female teacher and injuring another teacher and a classmate.
Police have detained the teenager, who is now being investigated for premeditated murder.
The incident occurred after the first class.
A 44-year-old teacher sustained a chest injury but is in stable condition, while an injured female student remains in critical condition.
State officials, including Prime Minister Robert Fico and President Peter Pellegrini, expressed deep concern over the tragedy, with the President warning against the rising culture of intolerance influencing youth.
Separately, a previous report detailed a shooting incident in Thailand, where a 14-year-old killed seven people including his grandparents and school staff using his grandfather's firearm.