NEW YORK (AP) - 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 inside a cement flower box outside the front door of the building.
After piecing together the shrapnel, police determined the devices were toy grenades that had been filled with gunpowder. Officers estimated that one was the size of a pineapple; the other the size of a lemon.
No timing device was used, Police Commissioner Ray Kelly said.
The blasts, which Kelly said happened around 3:35 a.m. (0735 GMT), shattered a panel of glass in the building's front door and ripped a 30-centimeter (1-foot) chunk from the planter.
"I heard a bang, that's it," said witness Ferdinand Pretd. "I came outside to check it out and I see nothing around, no flames, no smoke and that's it."
The British consulate is on the 9th and 10th floors of the building, the mayor said. He said he expected it would be open for business later in the day.
Offices of other foreign diplomatic representatives were checked as a precaution and nothing was found, Kelly said. Security videos in the area were being reviewed, he said.
In London, a Foreign Office spokeswoman, asked whether British authorities believed the blast was terrorism-related, said only: "Investigations are ongoing."
"We're not speculating about whether it's connected to the election," she added. Calls to the British Embassy in Washington were not immediately returned.
British Prime Minister Tony Blair is seeking a third term in office. With the country's economy doing well, Blair's Labour Party was widely expected to win despite anger over his support of the Iraq war.
The 14-story glass and metal building, on the east side of midtown Manhattan about a kilometer (less than a mile) from the United Nations headquarters, has retail shops on the lower level.
The closure of streets around the site caused some rush hour disruptions. For a few hours, trains on one subway line skipped the stop close to the site.