(TMZ) - Amanda Bynes is currently hospitalized on a 5150 hold after starting a small fire in the driveway of someone's home Monday night, TMZ has learned.

[PHOTOS: Amanda Bynes' Twitpics]

Law enforcement sources tell TMZ the fire department responded to the home in Thousand Oaks, CA last night, and called the sheriff's department after finding Amanda standing in the driveway next to the campfire.

Sheriff's deputies questioned Amanda about what she was doing, and why she was doing it -- and based on her answers they determined she needed to be hospitalized on a 5150 hold.

A 5150 hold is an involuntary hospitalization for mental evaluation. She can only be held for 72 hours though.

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