NEW YORK (CNN) -- A crude bomb made from a water bottle was used in an explosion that damaged a Starbucks coffee shop on New York's posh Upper East Side, New York police said. Monday's explosion shattered glass at the Manhattan Starbucks coffee shop. No one was injured. The Memorial Day explosion damaged the shop, but no one was injured and no motive has been identified for the bombing. "We believe it to be ... a six- to 10-ounce water bottle that was wrapped in black tape," New York Police Commissioner Ray Kelly told CNN on Wednesday. He said the bomb's powder may have come from fireworks components, including a fuse. The powder was placed inside the bottle in a way that made it "more powerful," Kelly said.
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New York police say the bomb outside a Starbucks was made from a water bottle
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The Memorial Day explosion damaged store but injured no one
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The blast happened about 3:30 a.m. on the posh Upper East Side of Manhattan
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Suspects and motive -- including possibility of political motivation -- still being sought
Kelly said the witness saw the two approach the @placeholder, then looked away.