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

Leroy Townsend, 53, was arrested May 18 after officers questioned him about possible narcotics violations. After spotting the dye-stained trousers, a second patrolman recognized Townsend from wanted photos broadcast on television, authorities said.

Townsend began his bank spree on Feb. 22 at the Conestoga Bank on the 1600 block of Walnut Street and on March 10 hit the same branch, said Jerri Williams, spokeswoman for the FBI.

Townsend then struck March 26 at the Firstrust Bank on the 1500 block of Market St., April 15 at the TD BankNorth on the 1600 block of Market, and May 16 at the HSBC Bank on the 1500 block of Market St., Williams said.

Townsend was charged Tuesday with four counts of bank robbery and one count of attempted bank robbery. He is being held on city charges pending transfer to federal custody, Williams said.

Contact staff writer Sam Wood at 215-854-2796 or at samwood@phillynews.com.