All of a sudden, we all heard this scream, this bloodcurdling scream, passenger Garnet Caton told CBC television.

The attacker was standing up right over the top of the guy with a large hunting knife — a survival, Rambo knife — holding the guy and continually stabbing him… in the chest area, Mr Caton added.

The attack continued as passengers fled the bus and waited for police on a desolate stretch of the TransCanada Highway near Portage la Prairie, Manitoba.

[…]

Sgt Colwell said the brave behaviour of the passengers and driver probably prevented anyone else from being hurt.

It's not something that happens regularly on a bus, said Colwell. You're sitting there enjoying your trip and then all of a sudden somebody gets stabbed. I imagine it would be pretty traumatic … the way they acted was extraordinary.

They were very brave. They reacted swiftly, calmly in exiting the bus and as a result nobody else was injured.