A 42-year-old Somersworth, N.H., man is facing charges he stalked a woman by following her via a global positioning system application in her cellular phone.

Police say Michael Barnes breached his bail conditions on an earlier assault charge when he enabled the GPS function in an attempt to determine the woman's location. He was arrested Saturday.

Foster's Daily Democrat says Barnes used the GPS to learn the woman was staying at a woman's shelter.

Court documents say the woman became aware she was being tracked when her phone carrier sent her a text indicating the GPS function had been activated. It listed Barnes' phone as having activated the GPS.

Barnes told a judge Monday he didn't know he had done anything wrong.