A youth has been arrested after a group of men including alleged gang members violently robbed a couple and struck one of them with a machete.
Police were alerted to the incident which occured on January 9 around 6pm at Stellin Memorial Park in the Wellington suburb of Northland.
The couple were sitting in their car in the park when they were approached by the men, some of whom were wearing Nomad gang patches.
A police spokesperson said one of the offenders demanded the man hand over his backpack.
"During an altercation over the backpack, the man sustained a serious injury to his leg, which required surgery. He was also allegedly punched a number of times."
The victims were also attacked with a machete.
At the time, police were able to recover the backpack and a 20-year-old was arrested in relation to the incident.
A 17-year-old has now been arrested and charged with aggravated robbery and will appear in the Wellington Youth Court on Tuesday.
The police said the investigation into the incident is ongoing and more arrests are inevitable, including a third suspect they have sufficient evidence to arrest.
"Police are also following strong lines of enquiry in relation to another offender, who struck the victim with a machete. This offender was believed to be wearing a Nomad gang vest."