A police helicopter has been called in during the search for a "high risk" missing man.

William Higgins was last seen at his home in Lanark on Sunday.

The 49-year-old, who lives on Auctioneers Way, is white, 5ft 9in and of medium build.

He is thought to be wearing jeans, brown leather walking boots and a black Berghaus jacket.

Inspector Ross McCallum said: "Since William was reported missing, officers have been carrying out extensive searches and enquiries to trace him.

"Local officers have been assisted by the police helicopter and marine unit during searches.

"William has been going through a difficult time recently and his family are growing increasingly worried about him as it is completely out of character for him not to keep in contact with his family or friends.

"We have recently received information regarding an unconfirmed sighting of Mr Higgins in the Clydesdale area on March 25.

"I would appeal to anyone in that area who recognises his description, or who has information that will assist our investigation to come forward to police."