A man who died at a tennis club in Auckland was a gentle, quiet scientist who was killed on his daily walk to look for insects and plants.

The suspected stabbing victim was in his early 50s and was a keen entomologist who worked in an office under the Blockhouse Bay Tennis Club seven days a week.

Gary Andrew, of the Whau River Catchment Trust, said he was sitting next to the man – who Herald have chosen not to name – every day at work.

Andrew said the victim left the trust’s office yesterday morning around 11.30am for his daily exploration of the neighbourhood.

“Someone attacked him, and at this stage we don’t know why,” he added Herald.

“We have no idea. I’m just assuming it was with a knife because he died pretty quickly. He went back into the (tennis club) and there was a lot of blood, and he’s died there.”

The victim was single with no children and his only known family was an elderly father in Queensland, Australia.

Andrew described him as eccentric, with a scruffy appearance that led some to assume he lived on the streets. In recent years, he had told colleagues that he suspected he was on the autism spectrum.

“He was a small, slightly built, well-spoken, educated, gentle guy who just would never hurt a fly. It just felt incredibly sad that something like this has happened. It’s so senseless.”

The victim was based at the foundation’s office but was not employed by them. He was previously at the University of Auckland and then did contract work for Landcare Research and other organisations. He had two degrees, in chemistry and philosophy, but his greatest passion was always insects and flora.

“He spends his whole life looking for them,” Andrew said. “He has nine new species named after him.”

“Every day he comes here to our office under the tennis club. He goes into the kitchen, makes himself breakfast, logs into iNaturalist, looks at the latest posts about insects and plants, then puts his laptop behind the bar and walks out. . .. to various places in Auckland looking for insects and plants.

“He comes back in the afternoon, puts them on iNaturalist, and that’s his whole life. And that’s what he did on Saturday. He left work like he does seven days a week, 365 days a year.”

Blockhouse Bay Tennis Club paid tribute to the man in an email to members on Sunday

“It is with a very heavy heart that we can confirm that we lost a beautiful soul at our club yesterday morning,” the club said.

“This individual was present at the club almost every day, working from his couch,” the email said. “He was a really sincere person who was always happy to talk to everyone.”

The club said it could not provide further details and the facility remained closed while police investigated.

“We know your thoughts are with the person’s whānau and all our members and teams who were present at the time of this terrible event.”

The police were today chasing a perpetrator who they believed left the area on foot.

Residents of the area said the attack happened in the middle of a busy Saturday at the club. The emergency services were called at 11.37 and up to 10 police cars rushed to the tennis club. The police Eagle helicopter hovered over the scene for an hour.

The emergency services found the man with serious injuries and despite ambulance efforts, he died at the scene.

Today, the club grounds and part of the Blockhouse Bay Recreational Reserve remained cordoned off. Officers could be seen scouring the grass, one of whom used a metal detector.

“This is an absolute tragedy, and investigators are working hard to determine the circumstances leading up to and following the murder,” Detective Inspector Glenn Baldwin said.

Ken Lau, who lives opposite the tennis club, said the attack happened in front of club members and people using the nearby reserve.

“The court was busy – it’s a busy, busy place on a Saturday. People playing tennis, bowling, cycling. There would have been a lot of witnesses.”

Lau did not witness the incident but went to the scene shortly afterwards.

“We’ve lived here for 30 years and we’ve never seen anything like this,” Lau said. “We’re scared, you know — it’s happening on our own farm.”

Police went door-to-door on the street looking for footage from residents’ security cameras. Lau said they had asked for footage between 11am and 12pm yesterday to check for people walking past the club.

Mr Baldwin said police collected CCTV, dashcam or security footage from the Blockhouse Bay area around 11.30am yesterday.

“Police would also like to speak to anyone who may have seen any suspicious activity around the Rathlin Street area.

“While we are open, police believe the offender may have left the scene on foot following the incident.

“We are providing support to those who witnessed what happened and we would like to speak to anyone who has not yet contacted us.”

– This story originally appeared in New Zealand Herald.