A Riverhead man was arrested on an outstanding warrant after his ex-girlfriend called police to tell them the man had let himself into her home and fallen asleep in her son’s bed early Friday morning, Southampton Town police said.

Police said 45-year-old Birtis Exum went into his ex’s Flanders Road house about 1:40 a.m. and went to sleep in her son’s bed. The woman turned on the lights and told Mr. Exum to leave, according to a police report. When he refused to, she called 911 and told police that Mr. Exum was trespassing at her home and that he had an active arrest warrant.

Southampton police arrived at the home and arrested Mr. Exum on the warrant for second-degree harassment, fourth-degree criminal mischief and second-degree menacing stemming from an incident on Jan. 31, police said.

He was taken to police headquarters and held for arraignment.