Detectives investigating the murder of Paul Olney in Wivenhoe, are appealing for witnesses regarding a taxi or private hire vehicle which was seen close to the murder location.
A black vehicle, believed to be Fiat or Nissan style, was seen at the junction of Denham Close and Clairmont Road at around 3pm on Monday, June 6.
It had four doors and appeared to have a white licence plate.
A man got in to the vehicle and police say they also need to find him.
He is described as white with a tanned complexion, 5ft 8ins tall, of average build, aged in his early to mid 20s. He had dark hair and black heavy stubble.
The man or anyone with information is asked to contact the Brentwood major investigation team on 101 or Crimestoppers anonymously on 0800 555 111.