According to Manigault's rep, "[she] is grateful for all of your prayers and asks for privacy at this time. Celebrations of [Duncan's] life, both private and public, will be announced at a later date."
A close friend tells ET that Manigault is "devastated" over the loss.
The Golden Globe and Oscar-nominated actor was born in Chicago and moved to Los Angeles in 1990, supporting himself as a bodyguard while pursuing an acting career.
His first roles closely resembled his day job, playing either guards or bouncers in films such as Back in Business, A Night at the Roxbury, The Players Club and Bulworth.
Soon he landed more meaty roles, playing Bear in Armageddon and finally portraying John Coffey in his breakout film The Green Mile (adapted from the Stephen King novel) for which he was nominated for both a Golden Globe and an Academy Award.