Up to 20 people stabbed at Pennsylvania high school

A teenager armed with two knives has gone on a rampage at a high school in the US state of Pennsylvania, injuring 19 students and a security guard.

The 16-year-old student was taken into custody at Franklin Regional High School in Murrysville, a suburb of Pittsburgh, police said.

The wounded, some with serious stab wounds to the torso, were as young as 14. Several were in surgery in hospital.

All are expected to survive.

Man in police custody after 4 co-workers stabbed in Toronto office

A male employee is in police custody following a stabbing that left four of his co-workers injured in uptown Toronto, police said.