Kain Parsons' father-in-law has spoken of family's loss after charity boxer's death

Kain Parsons was a "wonderful person" who will be sorely missed, his family says.

The grieving family of charity boxer Kain Parsons have spoken of their loss, saying they are going through a "very difficult time".

Parsons' life support was turned off in hospital on Wednesday after he suffered critical head injuries during the Fight for Christchurch event on Saturday night.

His father-in-law Dr Peter Benny today said 37-year-old father of three Parsons was a special person who would be sorely missed.

"All of us are devastated by the loss of such a wonderful person," he told Newshub.

"We are all going through a very, very difficult time but that's because Kain was such a wonderful man."

Benny said his son-in-law had set foot in the ring to fight for a children's charity.

"He felt that he was informed and knew what he was doing - he's just so driven to do good," he said.

It comes as Minister for Internal Affairs Tracey Martin has sought advice from her department about whether charity boxing matches should be better regulated.

"I've asked officials to give me advice on whether we can change the regulations, there are parts of this law that date back to 1908," she told Radio NZ.

"So there is a time to have a look at what we are doing here."

She said Parsons' death was a "tragedy" and the second in a charity event in the last three years.

Parsons' family earlier issued a statement through police.

"The family of Kain Parsons wishes to advise that tragically he has succumbed to the brain injury he received at the Fight for Christchurch on Saturday 3 November," it said.

"We wish to acknowledge and thank the amazing team in the ICU ward at Christchurch Hospital, the paramedics at the event, along with the many doctors, nurses and medical professionals who left their tables to quickly come to Kain's aid.

"The outpouring of heartfelt support from family, friends, colleagues and the public has been humbling and very much appreciated.

"Kain gave his life in the pursuit of raising money for those less fortunate and his enormous heart, selfless attitude and gentle giant nature will leave a void in the lives of so many.

"Kain is survived by his wife and three beautiful children who will miss their family man more than words can express."

A Givealittle page dedicated to raise funds for the Parsons family has already raised more than $51,000.