The American actress Amanda Bynes has been forcibly hospitalised for a mental health evaluation after she was seen with her trousers on fire in the driveway of a home in Los Angeles.

Police who responded to an emergency call said the 27-year-old started the fire herself with petrol and officers concluded she should be detained and evaluated for her own safety.

Celebrity gossip website TMZ reported that she was arrested after having previously rushed into a store in Thousand Oaks carrying her pet dog drenched in petrol.

In the 1990s, Bynes rose to prominence after appearing as a regular cast member on the Nickelodeon television series All That, The Amanda Show, and What I Like About You. In the 2000s, she entered the film industry, most recently appearing in teenage-oriented films Easy A. She has graced the cover of literally hundreds of magazines and was described by Maxim as “America’s Sweetheart”

The actress has had several recent run-ins with police.