A violent Wairarapa feud was reignited when a man brandished a large knife outside Masterton District Court.

Members of the public looked on yesterday as Lee Harris traded abuse with Warren Davies and his son Douglas Davies before Mr Harris allegedly pulled out the knife and invited them to follow him to a nearby park.

The incident took place in Church St outside Masterton's new temporary courthouse - and just metres from the Masterton police station.

The trio have a long history of enmity, and have previously clashed in incidents involving guns and knives.

Yesterday witnesses reported seeing Mr Harris drive slowly past the courthouse several times about midday. As he passed, he taunted Davies Sr and his son, who were standing at the entrance to the court.

Mr Harris stopped the car and was challenged to a fight by Warren Davies. Mr Harris got out of his car, showed a knife, and said: "Not here where there's people . . . follow me down to the park and we'll f...ing sort it out."

They continued to swear at each other before Mr Harris drove off.

Security guards and police arrived soon afterwards from inside the courthouse.

Acting Senior Sergeant Rob Rackliff said police were investigating the incident and were appealing for witnesses.

Yesterday's incident was the latest in a long line of run-ins involving the trio.

In 2007, Warren Davies told Wellington District Court he threw a hammer to try to knock a butcher's knife out of Mr Harris' hand during a fight.

He missed and Mr Harris and Douglas Davies clashed, both suffering stab wounds.

A jury acquitted the father and son of assaulting Mr Harris, but could not agree on a charge of assault with a weapon. No one was charged in connection with the stabbings.

After an incident in 2006, Mr Harris said Douglas Davies rammed his vehicle and tried to push it into the path of a bus in Masterton.

Mr Davies said Mr Harris had caused the crash, but was ordered by a judge to pay $2000 in damages to Mr Harris.

In 2002, Mr Harris said shots were fired from a car containing Davies and his son, and shotgun pellets were removed from his arm.

Davies and his son were charged with attempted murder, but the charges were dismissed when Mr Harris said he was not fit to give evidence.

- © Fairfax NZ News