Another Unprovoked Attack.

[Unknown Entity]

An eyewitness said the victim was stabbed 50 or 60 times by the man sitting next to him, who then severed his head with a large knife.

"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.

"When we came back on the bus... he was cutting the guy's head off and pretty much gutting him up," Mr Caton said.

The attacker ran at them, Mr Caton said, and they ran out of the bus, holding the door shut to prevent him getting out.

"He calmly walks up to the front [of the bus] with the head in his hand and the knife and just calmly stares at us and drops the head right in front of us," Mr Caton said.

"There was no rage in him ... It was just like he was a robot or something," he added.

The attack appeared to be unprovoked and it is thought the killer did not know his victim.

SOURCE: BBC NEWS | World | Americas | Passenger beheaded on Canada bus

What I don't get is why someone would attack and kill another without knowing the victim, who by witness accounts didn't provoke an attack. The way the guy acted like a "robot" worries me greatly. I'll think again next time I offer the seat next to me on the bus...

Are we going to all go mad, and crazed, like a robot and start stabbing people's heads off? What would drive someone to do that to another human being, provoked or unprovoked?