Mills, who also goes by the names Damon Hall, Devon Hall and Darren Mills, is the prime suspect in five bank robberies in the last 11 days.
Investigators say he has been caught on surveillance cameras numerous times.
The robberies occurred at the following bank branches:
Mills is described as a black male, age 43, 6'1" tall, approximately 280 pounds. He is considered armed and dangerous.
Anyone with information is urged to call the FBI at 215-418-4000 or the Philadelphia Police Department at 215-686-TIPS (8477), text a tip to PPD TIP (773847) or through PhillyPolice.com..
Police say there may be a reward for information leading to Mills' capture. Tipsters can remain anonymous.