The man who died after apparently being taken to hospital from the home of artist David Hockney is understood to be Dominic Elliott, one of the painter's studio assistants.
Mr Elliott, the subject of a Hockney painting in 2008, had sat for the 75-year-old artist on more than one occasion at his work space in Bridlington, East Yorkshire.
The 23-year-old had been hired from the local area and had assisted the artist with equipment on his latest projects, including last year's headlining Royal Academy show.
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Police say that anyone who sees Whitehouse should not approach him, but instead call them on 999 and quote incident 23 of 18 February.