Four people have been charged with murdering a 25-year-old man in Thetford.
Gym instructor David Lawal died from stab wounds after an attack in Brandon Road, on Thursday October 3.
He was found by the side of the road and despite efforts to save him by members of the public, police officers and ambulance staff, he was pronounced dead at the scene.
A Home Office post mortem examination concluded Mr Lawal died from a single stab wound to the neck and upper chest.
Detectives from the Norfolk and Suffolk Major Investigation Team have been working on a number of lines of enquiry to build a comprehensive picture of what happened in the hours leading up to the murder.
Police said Elie Saba, 33, of Goddards Way, Ilford, and three 17-year old males from Greater London have all been charged with murder and conspiracy to supply class A drugs.
They are all in police custody and due to appear at Norwich Magistrates Court on Friday morning.
A total of 16 arrests have been made.
A 21-year-old woman from Greater London and 17-year-old female from Thetford have been released on police bail, after being arrested on suspicion of murder, and conspiracy to supply Class A drugs.
A 20-year-old woman from Bedfordshire has been released on police bail after being arrested on suspicion of assisting an offender, and conspiracy to supply Class A drugs.
A 25-year-old woman from the Thetford area and a 22-year-old man from Haverhill, who were arrested on suspicion of assisting an offender, remain under investigation as enquiries continue.
A 42-year-old from Norwich and a 23-year-old from Haverhill arrested last month on suspicion of assisting an offender have been told no further action will be taken by police.
In addition, no further action will be taken against a man in his 60s from Thetford who was arrested on suspicion of assisting an offender.
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