LAWRENCE, Mass.—Police in Massachusetts say they caught a bank robber red handed—iterally.

On Monday, a man gave tellers a note threatening that he had a gun at a Sovereign Bank branch in Lawrence. Bank employees managed to hide a dye pack in the cash the robber stole.

Police Chief John Romero says the suspect was arrested in about an hour because an officer noticed red dye covering the man’s hands and some cash.

Fifty-year-old John Tripp was charged with armed robbery and held without bail for an arraignment Wednesday.

It could not immediately be determined if he has a lawyer. There is no public telephone listing for Tripp.