Youths who scaled the John Lewis and Marks and Spencer buildings in the town centre escaped from police.
About six young people were seen on the roofs at about 10.30pm on Saturday, March 1, and were believed to have climbing equipment, a police spokeswoman said.
A police helicopter scrambled to the area was sent back after the youths climbed down and escaped, she added.
No crimes were logged and no arrests were made.
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