Rugby great Jonah Lomu, the game's first global superstar whose speed and power terrorised opponents, died unexpectedly at the age of 40 on Wednesday.
Lomu had for decades battled the kidney disease that ended his playing career, but close acquaintances said his death still came as a shock.
According to AFP, he passed away suddenly at his Auckland home, family spokesman John Mayhew said.
"It was totally unexpected, Jonah and his family arrived back from the UK last night and he suddenly died this morning," Mayhew told TV3.
Mayhew, a former medic with the All Blacks, revealed Lomu's family were "going through a terrible time" before he broke down in tears.
New Zealand Prime Minister John Key also paid tribute, saying: "The thoughts of the entire country are with his family."
"(He)was a game changer whenever he stepped onto the field," he added.
Lomu played 63 Tests on the wing for New Zealand from 1995 to 2002, scoring 37 tries.
He rose to stardom at the 1995 Rugby World Cup, creating a new template for wingers which combined the speed of a backline player with the raw power of a forward.
Lomu scored seven tries in four matches at the tournament, including four in the semi-final against England.
At his peak, the 1.96 metre (six foot five inch) Lomu weighed 120 kilograms (265 pounds) and could cover 100 metres in 10.8 seconds.
Lomu was diagnosed in late 1995 with the rare kidney disorder nephrotic syndrome, which eventually cut short his international career.
He was inducted into the World Rugby Hall of Fame in 2011, with rugby's governing body saying he had left an indelible mark on the Rugby World Cup.
World Rugby chairman Bernard Lapasset said in a 2013 documentary that Lomu revolutionised the sport at a key juncture when the game was turning professional.
Former Wallaby Tim Horan said Lomu's status in the game never went to his head and he was the first to walk into the dressing room to shake an opponent's hand.
