A serial bank robber believed to be responsible for five Center City heists was captured after Philadelphia police stopped the man during a drug sweep and noticed red dye on his pants, authorities said.

Leroy Townsend, 53, was charged Tuesday with four counts of bank robbery and one count of attempted bank robbery. He was arrested Sunday after officers questioned him about possible narcotics violations. After spotting the dye-stained trousers, a patrolman recognized Townsend from wanted photos, authorities said.

Townsend began his bank robberies on Feb. 22 at the Conestoga Bank on the 1600 block of Walnut Street and hit the branch again on March 10, said an FBI spokeswoman. Authorities said he then struck the Firstrust Bank on the 1500 block of Market Street on March 26, the TD BankNorth on the 1600 block of Market on April 15, and the HSBC on the 1500 block of Market on May 16.

He is being held on city charges pending transfer to federal custody, Williams said.

- Sam Wood