Selena Gomez -- Trespasser Arrested At Singer's Home ... Cops Roll On 911 Call

1:20 P.M. PDT -- Police tell TMZ the suspect has been arrested for trespassing. It's not known if Selena was at home during the incident.

12:44 P.M. PDT -- Law enforcement tells TMZ the suspect has been detained and is currently being questioned about what he was doing at Selena's home.

Cops swarmed around Selena Gomez' Calabasas home Friday morning after someone reported a suspicious person ... law enforcement sources tell TMZ.

Someone at the scene tells TMZ ... a man jumped a fence onto her property but it appears he was not a burglar ... more like a trespasser.

Selena has had her problems with unwelcome visitors. A guy was convicted in February after trespassing at her old house. He was sentenced to 120 days in jail.

And on March 31st ... another man was arrested on Selena's property while she was home. The guy rang the doorbell and asked the person who opened the door if Selena was home. He had broken into her guest house and was arrested for burglary and trespassing. It's unclear if he's still in custody.