The robbers were understandably frightened to be surrounded by dozens of policemen. But Instead of surrendering, they decided to go out in a blaze of glory, and fled the building while shooting at everything in sight. The policemen ducked, covered, and shot back. Two running robbers were fatally injured, and the third was wounded.
Why was the gunfight over so quickly? The three robbers were carrying REAL guns loaded with FAKE ammunition. They were firing blanks, making enough flash and thunder to fool the police into shooting back, but not enough to actually help them escape.