Police in New York will board city buses and subway trains and teach passengers how to recognise suicide bombers, officials said on Thursday in the wake of the deadly blasts blamed on such bombers in London. [snip] "People could be told to look out for bulky clothing in warmer weather, or people repeatedly returning to a package," said Police Department spokesman Paul Browne. [snip] "When you catch a potential terrorist, he doesn't have a map of a cornfield, he has a map of New York City or a building," the mayor [Bloomberg] said.