Actress Amanda Bynes, 28, was arrested early Saturday morning for driving under the influence, according to reports published by E! Online.

Bynes was traveling west in her Mercedes on Riverside Drive in the San Fernando Valley of California at approximately 3 a.m. on Saturday. She stopped at a red light at the intersection of Riverside and Van Nuys Boulevard — but stopped for the red light in the middle of the intersection, according to authorities on the scene.

The troubled actress was then promptly pulled over by the California Highway Patrol for suspected impaired driving.

She was then “given a series of field sobriety tests, which she was unable to complete,” according to an incident report. The same report described her appearance as “disheveled.”

After her inability to complete the tests, CHP transported her to its West Valley Office to meet with a drug recognition officer.

According to TMZ, this officer identified her as being under the influence of a “stimulant.” E! Online reports that the substance is “unknown.”

Bynes was then booked for driving under the influence.

She posted a $15,000 bail and was released at 12:44 p.m. the same day.

This could spell trouble for Bynes, as she is currently under probation for a DUI charge she received in 2012. In February, she was placed on three-years’ probation for the charge, and was ordered to complete a three-month alcohol education program.

Last year, Bynes was a prominent figure in headlines for her erratic and inexplicable behavior, including making dramatic changes to her appearance, bullying high-profile celebrities on Twitter and setting small fires in her parent’s neighbor’s driveway.

On July 22, 2013, the Easy A star was placed on a 5150 involuntary psychiatric hold. She was later released from the facility in December of the same year, and placed under the stewardship of her parents.

At the time, many in the media speculated that she was experiencing schizophrenia, prompting Bynes’ lawyer to issue a statement back in April.

“There has been much speculation about Amanda’s medical condition,” said her attorney, Tamar Arminak. “She has remained silent because she believed it was best to keep her mental health diagnosis private.”

Amanda Bynes is scheduled to appear in court on Oct. 23 to face Saturday’s DUI charge.