Director-actor Rob Reiner and his wife Michele have been found dead at a Los Angeles home owned by Reiner, according to a law enforcement official briefed on the investigation.

Investigators believe they suffered stab wounds and a family member is being questioned by investigators, the official said on Sunday.

The Los Angeles Fire Department said it responded to a medical aid request shortly after 3.30pm and found a 78-year-old man and 68-year-old woman dead inside.

Detectives with the robbery homicide division were investigating an “apparent homicide” at Reiner’s home, said Captain Mike Bland with the Los Angeles Police Department.

Los Angeles authorities have not confirmed the identities of the people found dead at the residence in the upscale Brentwood neighborhood on the city’s west side that’s home to many celebrities.

Reiner was long one of the most prolific directors in Hollywood, and his work included some of the most memorable movies of the 1980s and ’90s, including “This is Spinal Tap,” “A Few Good Men,” “When Harry Met Sally” and “The Princess Bride.”

His role as Meathead in the 1970s TV classic “All in the Family” alongside Carol O’Connor’s Archie Bunker catapulted him to fame and won him two Emmy Awards.

Reiner turned 78 in March.

Los Angeles mayor Karen Bass called Reiner's death a devastating loss for the city.

“Rob Reiner’s contributions reverberate throughout American culture and society, and he has improved countless lives through his creative work and advocacy fighting for social and economic justice,” Bass said in a statement.

“An acclaimed actor, director, producer, writer, and engaged political activist, he always used his gifts in service of others.”

The son of comedy legend Carl Reiner, Rob Reiner was married to photographer Michele Singer Reiner since 1989.

The two met while he was directing “When Harry Met Sally” and have three children together.

Reiner was previously married to actor-director Penny Marshall from 1971 to 1981.

He adopted her daughter, Tracy Reiner.

Carl Reiner died in 2020 at age 98 and Marshall died in 2018. (AP)