A 29-year-old Onset man was arrested Thursday charged with unlawful sexual surveillance for allegedly using a cell phone to photograph a woman.

Police responded to the Wareham Crossing shops on Wednesday, April 6 at approximately 4 p.m. after receiving a call that a man was taking “up skirt” pictures with a cell phone.

According to police, Gregory Allen Mattos, who is listed as a level two sex offender, fled the store when the woman he allegedly photographed became startled.

Following a joint investigation by detectives from Wareham, New Bedford and members of Wareham’s Violent Fugitive Apprehension Section, Mattos was arrested at approximately 1 p.m. the following day.

Police said Mattos was currently on bail for a charge of failure to register as a sex offender on a previous, unrelated case.

Mattos was arraigned Friday morning in Wareham District Court on the unlawful sexual surveillance charge. Mattos’ prior bail was revoked and he was ordered held on $7,500 cash bail for the new charge.

Mattos is scheduled to appear in court on May 9 for pretrial proceedings.