Four victims, including a teacher and three children aged 5, 8 and 11, were killed in a shooting at a primary school in the US state of Oregon, local police say.

A 16-year-old suspect forced his way into the school by firing at locked doors. He was also killed in the shooting by an armed member of the community who followed the suspect inside the school, police said at a press conference.

Two additional victims, a 7-year-old and another teacher, were hurt and transported to hospital in critical condition.