Two further arrests have been made following the fatal shooting of Patrick Anzy in Dalston, east London.
A 33-year-old man was arrested in the early hours of Saturday, May 15 on suspicion of murder.
A woman aged 38, was also arrested on suspicion of assisting an offender.
Both were arrested in the Birmingham area with the assistance of West Midlands Police and remain in custody.
A teenage boy and a 25-year-old man were arrested earlier this week on suspicion of conspiracy to commit murder and have been released under investigation.
A murder probe was launched after 31-year-old Patrick Anzy was found seriously injured in Gillett Square at 12.56am last Saturday.
He was pronounced dead at the scene.
A post-mortem took place on Tuesday and confirmed the cause of death was injuries from gunshots.
The Metropolitan Police’s Detective Inspector Andy McDonald said: “This investigation is making progress, evidenced by these arrests, but I am still very keen to speak to anyone who was in the Gillett Square area at the time of the shooting who may have witnessed the murder.
“Patrick was attacked in Boleyn Road, N16, in the early hours of Saturday, 8 May and, at the time, I believe there may have been a number of people around who may have seen or heard something.
“Any information, no matter how small, could prove to be crucial to this investigation and help secure some justice for Patrick’s family.”
Anyone with information or any witnesses are urged to call 101, reference CAD 412/08May. To remain 100 per cent anonymous, please contact Crimestoppers on 0800 555 111.