From Associated Press:
WINNIPEG, Manitoba - A passenger sleeping on a Greyhound bus was killed and decapitated by his seatmate on Wednesday night as the vehicle rolled across the Canadian prairies, witnesses said.

"All of a sudden, we all heard this scream, this bloodcurdling scream," said Garnet Caton, who was sitting just in front of the victim, in an interview with CBC Television.

"The attacker was standing up right over top of the guy with a large hunting knife — a survival, Rambo knife — holding the guy and continually stabbing him, stabbing him, stabbing him in the chest area," Caton said.
The attack continued as other passengers fled the bus and waited for police on a desolated stretch of the TransCanada Highway near Portage la Prairie, Manitoba, said Caton, who helped bar the bus door to prevent the attacker from leaving.

'No rage in him'
"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," Caton said.

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

Caton said the victim was stabbed up to 50 times.

A Royal Canadian Mounted Police officer said the attack occurred while the vehicle was en route from Edmonton, Alberta, to Winnipeg, Manitoba.

CBC reported the Royal Canadian Mounted Police took the attacker into custody.

Authorities declined to provide other details of what they described as a "major incident."