BELLEVUE, Wash. -- Police used a robot to blow up a backpack on Friday that was left in a bank driveway by a robber who said it contained a bomb.

The incident began when a man robbed a Washington Mutual Bank branch at 10550 Northeast 8th St. at about 10:30 a.m. Officers captured a suspect, who told them there was a bomb in his backpack.

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Officers cut the backpack loose, leaving it in the bank's driveway.

Police kept a block around the bank closed while officers took a close look at the backpack.

Police closed nearby streets and some buildings were evacuated while a robot was sent to examine the backpack. At about 12:12 p.m., the backpack was blown up, sending its contents flying onto the street.