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Police say road rage appears to have prompted the attack in broad daylight on Saturday - they do not believe the groups were known to each other.
Nobody has been arrested yet but police have located two vehicles of interest, Detective Inspector Graham Pitkethley said in a press statement this afternoon.
"We want to hear from anyone who saw a white Mazda Bounty ute carrying a trail bike, and a black Volkswagen Amarok ute travelling from Te Awamutu to Ōtorohanga between 5pm and 6.20pm on Saturday night," Pitkethley said.
"We would also like to thank all of the people who have already come forward with information which is proving extremely helpful as we build a picture of what occurred."
The scene examination on Maniapoto St had finished but extra police remained in the area.
Victim was 'very positive role model'
Police were called to Maniapoto St, one of Ōtorohanga's main roads, around 6.30pm on Saturday.
A witness told the Herald he saw two patched gang members hit the man, causing him to collapse, as families looked on in horror.
"This was an incredibly violent attack in a very public place, and we want to let our Ōtorohanga community know we're clearly focused on identifying and locating those involved," Pitkethley said in an earlier statement.
A person who knew the man but asked not to be identified described him as a good, hard-working person.
"He had his own business and was a father and left kids behind and a wife," the person told the Herald. "He was a very positive role model in the neighbourhood."
Police remain at the scene today as the investigation continues, with a section of Maniapoto St at State Highway 3 cordoned off and closed to traffic. Authorities have urged anyone with information about the incident to contact them - either by calling 105 and quoting file number 211002/2797 or calling Crime Stoppers anonymously at 0800 555 111.
A witness told the Herald yesterday he pulled over after noticing a fight unfold outside the Mobil service station.
"It was these two gang members and they were attacking this [man] ..." he said. "They hit him on the head and it just dropped him cold and they just took off. Pretty shocking really."
The witness told the Herald that the gang members fled in a white Rodeo ute.
A friend of the victim was also on the scene, the witness said.
"He was with his mate, he had a motocross bike on the back [of their vehicle], they looked like they had just been out for the weekend sort of thing," he explained.
"He didn't get involved, he stepped back ... they had their patches on and everything. Just your classic sort of thug."
The witness said he then got out of his car to assist the badly injured man who he says was wearing high-vis clothing and didn't look like a gang member.
"I got out and ran back down and there was a young family there and a couple of other people," the witness said.
"I stopped actually and tried to get that guy on his side. Get him in the recovery position," the witness said.
"There was a fair bit of blood [but] it actually didn't look that bad. I sort of thought he'd bounce back.
"I thought he was knocked out, I thought he'd come back."
Police were called to Maniapoto St around 6.30pm to reports of a large group of people fighting.
The witness said within about five minutes of the attack numerous carloads of people had turned up who seemed to know the man and were getting very angry.
"There were a few people around and then it all sort of kicked off," the witness said.
"It looked like all his family and all his mates were coming down and they were spewing, they were smashing **** on the ground and yelling and I thought I'm just going to get out of here," the witness said.
"People knew him in the area I think a phone call got put out. Within five minutes like 10 carloads of people had pulled up."
The witness said the incident did not reflect the town of Ōtorohanga.
Hours after the Ōtorohanga incident, Waikato police were also called last night to a shooting incident in Paeroa, about 120km away.
A man was airlifted via Waikato Westpac Rescue Helicopter to Waikato Hospital for injuries described by police as minor.
Authorities said he suffered a firearms-related injury around 9pm at a Paeroa address.
"Police inquiries are ongoing to understand the circumstances and identify those involved," a police spokesperson told the Herald.
