A neighbour, who asked not to be named, was outside gardening when he heard a loud crash.
"A tractor had gone through to the next door neighbour's house, and a boat and trailer it was towing had become detached.
"The gentleman on the tractor had fallen off and was on the ground. He was conscious and I asked him if was able to breathe properly, he was struggling but was able to breathe."
He said the man's wife and daughter rang the ambulance.
"I stayed with them for a while and waited for the emergency services to arrive."
Another neighbour, John Govier, was driving to town with his wife when they saw two fire engines at the property.
"We thought it was pretty serious because an ambulance came flying down the road and then two police cars and another ambulance," he said.
David Paterson's wife Sheryl (right) and daughter rang the ambulance.
"It's a terrible thing to happen. His poor wife must have been absolutely beside herself."
Govier said Paterson, who worked part-time at the local Bunnings, had been trying to start a tractor used to tow boats when the accident happened.
"It was in gear and of course, it jerked forward and threw him and then ran over him."
Sheryl Paterson was shaken up by the tragedy and last night family and friends had gathered at her home to comfort her.
Last night, condolence messages were posted on son James' Facebook page.
"R.I.P my friend, I will help all I can to look after Sheryl, part of me goes with you," wrote Kelvin Williams.
"Condolences mate, thoughts are with you and the whanau," added James Wheeler.
Paterson was a member of the Waikanae Boating Club, and treasurer John Jones last night said he was "easy-going, very helpful and friendly ... nothing was a problem.
"He liked a good laugh ... it's a real tragedy," he said.
Police spokesman Guy Callaghan said it was not yet known how the man came to be under the tractor and trailer.
