Alaska State Troopers say a man with a knife tried to enter a rural school and stabbed two people outside.

Authorities say the principal at Kotlik School locked it down Friday just before 19-year-old Rick Andrews reached the front door.

Troopers say Andrews pounded on the door, threatened to kill the principal and tried to get inside through windows and another door.

A man and a woman approached Andrews and attempted to intervene.

Troopers say he stabbed both in the torso but one person wrestled away the knife.

Two other residents restrained Andrews until troopers arrived. The injured residents were flown to a hospital.

Andrews is charged with felony assault.

He is represented by the Alaska Public Defenders Office, which did not immediately respond to an email request for comment