The family of missing BBC presenter Mark Speight, whose fiancee recently died, have urged him to make contact.
The 42-year-old SMart host quit the show following the "tragic loss" of fellow presenter Natasha Collins, whose body was discovered at the north London flat they shared in early January.
He was last seen on Chamberlayne Road, Kensal Rise, north-west London on Monday afternoon and was reported missing by friends after failing to arrive at a meeting in Covent Garden at 15:30 BST.
A statement from the families of Speight and Ms Collins said they were "deeply concerned" for Speight and added "please get in touch".
"Mark has not been seen since 13:00 BST yesterday [Monday] and because of his fragile state of mind both Mark's family and Natasha's family as well as all of his friends are deeply worried," it continued.
"We notified police because of our concerns and we just want to know he is safe. We would urge Mark, if he hears this appeal, to get in touch."
Speight was initially arrested on suspicion of murder and supplying cocaine after his fiancee's body was found and bailed until the beginning of February, though no charges were ever brought.
It was revealed last week that Ms Collins died in the bath after taking cocaine and sleeping pills.
The 31-year-old, who met Speight while filming the BBC children's show See It Saw It, was found with hot water burns on her body, face and tongue.
Westminster coroner Paul Knapman recorded a verdict of death by misadventure and gave the cause of death as cocaine toxicity and immersion in hot water.