A man who prosecutors say robbed one bank, and tried to rob another on the same day, was arrested shortly after a retired police officer took a photo of his getaway vehicle.

According to Somerset County prosecutors, Douglas Conroy, 60, entered Provident Bank in Bridgewater Monday and demanded money, but the teller walked away and Conroy left without any cash.

Nearly three hours later, prosecutors say Conroy went to a Somerville bank and left with an undisclosed amount of cash.

But the retired officer, who happened to be at the bank, followed Conroy to his car and took a photo of it as Conroy drove off.

Police caught up to Conroy near a third bank, but he was taken into custody.