NEW YORK - Two makeshift grenades exploded outside a building housing the British Consulate early Thursday, Election Day in Britain, causing slight damage but injuring no one, officials said. Officials stressed that it was not clear whether the consulate itself had been targeted. The midtown Manhattan office building houses a variety of domestic and foreign companies. "We do not at this point have any idea who did it or a motive," Mayor Michael Bloomberg said, adding the explosion was caused by "a relatively unsophisticated explosive device." There were no threats or phone calls, he said. The grenades had been placed...