A man has been arrested in Trinidad on suspicion of murdering Jordan Maguire from Marsh Farm.
Jordan, 20, was stabbed to death in his Thrales Close home on May 26 this year.
Detectives from the Major Crime Unit, with assistance from the Crown Prosecution Service and National Crime Agency, have been liaising with the Trinidad and Tobago Police Service over the last fortnight.
On Wednesday night, 30-year-old Jason Nelson, a Grenadian national formerly living in Luton, was arrested by the TTPS on behalf of the MCU.
There will now be a process of extradition from Trinidad, which could take a number of months.
The MCU are still keen to hear from anyone who may have information that could help this investigation and the team can be reached directly at their base on 01707 355666.
Alternatively contact 101, the police 24 hour non-emergency number or independent charity Crimestoppers on 0800 555111.