Three teenagers have been arrested after allegedly fighting on a train and then robbing another group of people in Glen Eden.
The trio allegedly took part in a fight on a train last Monday and got involved in another dispute at a nearby location before allegedly attacking and robbing another group of youths just after midnight, police say.
The trio approached the other group of four people as they walked home on West Coast Rd.
They allegedly threatened and then attacked with kicks and punches before making off with one of the group's bags, police said.
After executing search warrants yesterday, police arrested three people aged between 15 and 18.
Two now face aggravated robbery charges and will appear in the Waitākere District Court today.
A third person has been referred to Youth Aid.
Inspector Stefan Sagar said he wanted "to reassure the Glen Eden community, and all communities, that this type of behaviour will not be tolerated".
"We encourage anyone who witnesses a crime or anyone who at any point feels unsafe to contact Police and call 111 immediately. We are here to help."