It happened at the old Philadelphia Inquirer printing plant at 800 River Road on Monday, Oct. 16, authorities said.
A witness saw a man on the roof just before 10 a.m. and called police, but the man spotted the witness fled across the roof, according to the department.
Arriving police said they found signs of a break-in as well as tools and equipment "commonly used (...) to steal copper."
Canine units and a drone were called to assist as police searched the building for an hour and a half, but the pair were only discovered when an officer noticed an unsecured latch on a roof HVAC unit and looked inside, UMPD said.
Each man was charged with burglary, criminal trespassing, and related offenses, according to authorities. Their names were not reported.
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