The gang members were found guilty of stabbing Kamali Gabbidon-Lynck to death in Wood Green last year while the victim was trying to save a friend the group had also targeted, according to judicial authorities.
The convicted killers – two men and three teenagers – reportedly attacked officers after they were ordered to serve a total minimum of 116 years in prison on Monday.
People in the public gallery also had to be restrained from jumping down into the well of the court, according to the BBC.
Four custody officers were hospitalised for minor injuries following the incident, which was “quickly resolved”, a HM Courts and Tribunals spokesman said.
Three arrests were made, according to a City of London police spokesperson.
Gabbidon-Lynck was murdered last February after trying to stop the defendants from stabbing and shooting his friend, according to police.
He drove his car into the Tottenham-based gang members during the attack and then fled to a hairdressers’.
The defendants followed Gabbidon-Lynck and stabbed him to death, the Metropolitan Police said.
Catherine Gould from the Crown Prosecution Service (CPS) said one of the culprits was stopped by police shortly after and “had the audacity to tell officers that he hoped they would cut down on knife crime”.
She said it was a “tragic case of gang rivalry”, adding: “It must not be forgotten that were it not for the actions of Mr Gabbidon-Lynck, his friend may well have lost his life too.”
The defendants – 21-year-old Sheareem Cookhorn, 18-year-old Tyrell Graham, and 17-year-olds Jayden O’Neill-Critchlow, Shane Lyons and Ojay Hamilton – were all found guilty of murder and handed life sentences on Monday.
Cookhorn was given a minimum sentence of 28 years and Graham a minimum sentence of 25 years, according to the CPS.
All three teenagers were ordered to serve at least 21 years in prison.
Detective Chief Inspector Simon Stancombe said Gabbidon-Lynck and his friend – who has been left with life-changing injuries following the attack – were targeted by the group “with a ferocity [he has] rarely seen”.
“I want to pay tribute to Kamali’s family who throughout this trial have maintained their dignity in very difficult circumstances,” he said.