http://www.cbc.ca/canada/new-brunswick/story/2007/05/03/nb-catsecurity.html

Fair use excerpt:

A cat that travelled from Quispamsis, N.B., to Ontario stowed away in
a suitcase was not a violation of airport security rules, according to
the authority that oversees security at Canada's airports.

Anna-Karina Tabunar of the Canadian Air Transport Security Authority
said Ginger the cat wouldn't have been allowed to travel in the cargo
hold of a flight from Saint John to Toronto had airport staff known
she was there, but the fact she passed through security doesn't
indicate a problem.

(Note before viewing the rest of the story: the cat was discovered by
the owner when she opened her bag at the hotel - allegedly the cat was
a self-imposed "stowaway", not intentionally packed by the owner into
the suitcase.)