Police have named the man they are hunting over a double shooting which left a police officer dead and another man injured.
Essex Police identified the alleged gunman as Peter Reeve, described as white, aged 64, about 5ft 10in with short greyish hair and issued a photograph of him.
He is wanted over the shooting in Redbridge Road, Clacton, earlier on Monday.
The man who died was an off-duty police officer, named locally as Pc Ian Dibell, who lived nearby.
A police spokesman added: "He (Reeve) is wearing jeans and possibly with glasses. He comes from the Clacton area."
Chief Constable Jim Barker-McCardle is due to hold a press conference at the force's headquarters in Chelmsford later on Monday.
A spokesman said: "Residents are being urged to remain indoors while armed officers locate the gunman. Neighbourhood policing officers are maintaining a high-profile and visible presence in the community, supporting victims and witnesses.
"Members of the public are urged to contact police on 999 if they see the gunman who should not be approached."
Paul McKeever, chairman of the Police Federation of England and Wales, paid tribute to Pc Dibell, saying: "This is extremely tragic and devastating news. Police Constable Ian Dibell demonstrated remarkable courage and bravery whilst off-duty and has paid the ultimate price.
"The thoughts of the entire police service are with his family, friends and colleagues at this very difficult time."