Amanda Bynes in 5150 hold after lighting elderly woman's driveway on fire

Amanda Bynes is currently hospitalized on a 5150 hold after starting a small fire in the driveway of a stranger's house Monday night, TMZ reported.

An elderly woman whose house was the spot where Amanda Bynes had her latest "behavior" spoke to TMZ, saying she had no idea what was going on until the police knocked on her front door.

The police reportedly asked her "Do you know anyone by the name of Amanda Bynes, or why she would have some vendetta against you?"

Amanda Bynes is now in a 5150 hold, which is involuntary hospitalization for mental evaluation. Amanda can only be held for 72 hours.

Law enforcement sources said the fire department responded to the home in Thousand Oaks, CA around 9 PM -- near where Amanda was just accused of trespassing -- after someone noticed the small blaze in the driveway.

The sheriff's department was subsequently called when Amanda was found standing near the campfire. The police told the woman that a young lady [Bynes] was seen in her driveway making the fire with a "little red gas tank."