Police are searching Garston and north Watford after a vulnerable man went missing.
Jason Grant, 42, was last seen at his home in Coates Dell, near Garston Park, at around 8pm yesterday.
Hertfordshire Constabulary launched a search for him this afternoon, with police helicopter broadcasting from loud speaker over Garston Park.
Officers are concerned for Jason's welfare and asked anyone who has seen him in the last 24 hours to get in contact.
He is described as a 5ft 9in tall, with a stocky build and mousey cropped hair. At the time he disappeared Jason was s wearing a green jacket with a burgundy back panel, dark blue jeans and black leather boots.
Police said he may also be carrying a burgundy rucksack which has blue straps.
Officers said Jason often frequented woods in the area and asked that dog walkers and ramblers be particularly vigilant.
Anyone with information about Jason’s whereabouts is asked to contact the police via the non-emergency number 101.