The police have issued CCTV stills of missing BBC presenter Mark Speight entering a London train station on the day he was reported missing.
The 42-year-old SMart host quit the show following the "tragic loss" of his fiancee, fellow TV presenter Natasha Collins, whose body was discovered at the north London flat they shared in early January.
He was last seen boarding a southbound Bakerloo line train on the London underground heading for Paddington at 14:47 BST on Monday, having withdrawn money from a cash machine close to the station at 14:18 BST.
He was reported missing by friends after failing to meet a family member in Covent Garden at 15:30 BST.
Detective Inspector Declan Williams, from Enfield CID, based at Edmonton police station said: "Mark's friends and family are extremely concerned for his welfare and they continue to agonise over his disappearance. Since appeals have been issued, a number of people have spoken to us, providing vital information."
He added: "Did you see him travelling, do you know where he was heading? I urge anyone with information to contact Enfield police station on 0208 807 1212".
Speight was seen wearing a brown suit jacket over a light hooded sweatshirt, dark blue jeans and a brown flat cap and was carrying a dark satchel bag.
A statement from the families of Speight and Ms Collins said they were "deeply concerned" for Speight and added "please get in touch".
"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.