Essex Police have taken the "unusual step" of issuing the names and photographs of Jack Hummerstone, 18, from London, and Andre Vella, 19, from Frinton-on-Sea, and are urging anyone who knows anything about their whereabouts to contact police immediately.
Thomas Brittain, 26, from Essex, died after he was assaulted in the home of a friend, in a flat in Parkside Quarter, Colchester, at around 1.45am on Saturday.
He suffered multiple stab wounds and the provisional result from the post-mortem examination carried out is that he died from a stab wound to the chest.
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The Royal London Hospital and Newham University Hospital have been declared inadequate by the Care Quality Commission.
Homes have been evacuated as the Army works to defuse an unexploded World War II bomb discovered near Wembley Stadium.
The strike threat came just minutes after a national rail strike planned for Monday was called off.