New Zealand Prime Minister Christopher Luxon has joined the condemnation of the "run it straight" rugby tackle challenge that has gone viral on social media after a teenager died from a serious head injury earlier this week.

A 19-year-old New Zealander has died of a "serious head injury" sustained in a social media-inspired game of tackle with friends, police said. The young man, identified in local media as Ryan Satterthwaite, died in hospital on Monday after a game of "run it straight" in the city of Palmerston North.

A teenager has died in New Zealand after taking part in a rugby-based craze that has been described as “bull-rush on steroids”.