An 18-year-old attacked at least four people with a knife at a high school in Cheongju, South Korea

<p>The attack occurred Monday morning, when an 18-year-old student stabbed several people, including the high school principal, who suffered serious injuries. Police were alerted at 8:36 a.m., and the suspect was quickly apprehended after attempting to flee. The other victims suffered minor injuries and four weapons, including a box cutter, were found on the assailant. Authorities are investigating the motives behind the attack, which comes shortly after a similar incident in which a teacher stabbed a young girl to death.