Three patched Tribesmen gang members are facing charges after being arrested in relation to a serious assault on the Waikato Expressway.

Seven search warrants, four in Auckland and three in Christchurch, were executed on Tuesday morning following an investigation into the March incident.

As a result, four men, all tribesmen members, were arrested, says Detective Senior Sergeant Stephen Ambler.

"A large amount of gang insignia was seized including clothing, patches and helmets as well as cell phones and two motorcycles.

"Three men, aged 25,27 and 32 have been charged with wounding with intent to cause grievous bodily harm in relation to the serious assault on the Waikato Expressway on March 11.

"One of these men also faces charges of possession for supply of cocaine and possession of ecstasy."

Stephen says cannabis and cash were also located as a result of the searches.

The accused appeared in the Christchurch District Court and Counties Manukau District Court on Tuesday afternoon.

The fourth man was arrested on an unrelated matter.

The 31-year-old victim from the assault is continuing to recover, says Stephen.

"I would like to thank all those involved including those members of the public, who like the NZ Police will not be intimidated or tolerate gang violence.

"Some long hard hours went into today's termination by a lot of staff over several districts, while a lot of this work goes unseen and is unheralded it none the less is impressive.

"Although Tuesday's arrest was a significant milestone in the investigation there is still a lot to be done.

"We know of up to six other people who were involved in the assault and we will continue to work towards bringing all those responsible to justice."

The investigation team continues to review information provided by the public and anyone who is yet to contact police is urged to come forward and contact us anonymously through Crime Stoppers on 0800 555 111 quoting file number 220311/5636.