Police in southern Vietnam on Sunday arrested a 15-year old boy who allegedly stabbed two other teenagers with his switchblade, killing one and severely injuries of the other.
Tran Quoc Hung, a high school student in Dong Nai province, was arrested by police at his house as he was changing clothes and about to run away, the police said.
The two victims, Pham Tran Le Phuoc Tai and Nguyen Ngoc Phuoc, were both 16.
Witnesses said Tai and Phuoc were drinking coffee at a cafeteria when they suddenly became embroiled in a conflict with Hung.
Hung stabbed Tai in the chest and killed him immediately.
Phuoc, who tried to subdued Hung, was stabbed twice. Doctors said he sustained severe lung injuries and is in critical condition.
It is still unknown what caused the conflict.
Investigations are ongoing.