Public Safety Minister Stockwell is expressing shock at what he calls a "horrific" bus stabbing that he's calling one-of-a-kind in Canadian history.

Day was reacting to what witnesses say was a savage knife attack on a Greyhound bus in Manitoba that resulted in a person being killed and later beheaded.

Day, in Levis, Que., for a summer planning session of Conservative MPs, says the full weight of the law must be brought to bear on the perpetrator.

But he says such an incident is, thankfully, extremely rare - in fact he's calling it "probably one-of-a-kind in Canadian history."

Day says he wouldn't even entertain the notion of registering knives as dangerous weapons, noting that millions of kitchen knives alone are likely sold each year.