One of the men who desperately tried to lift a runaway police van off a pensioner trapped underneath it in a busy park has told of his horror as the tragedy unfolded.

The incident claimed the life of a local grandad, believed to be in his 80s, as crowds of people were enjoying the sunshine in Pudsey Park, off Church Lane, Pudsey.

Bouquets of flowers and tributes mark the spot where the empty police van, which had been parked on a downward slope inside the park’s Church Lane entrance, rolled forward on Saturday, before colliding with the man who had been seen walking up the hill on his way out.

Cards left with the flowers named the victim as Donald, with messages from his family, including grandchildren, which read: “Miss you loads. Love you forever and always.”

Another read: “Sadly missed. You just went for a walk in the park.”

One of the men who rushed to help, as the van “free-wheeled” down the hill, said he had been watching a young policewoman who arrived alone in the van to sort out trouble with two rowing families before the tragedy at 2.15pm on Saturday.

“Things had calmed down a bit and she went back to the van, opened the driver’s door as if she was trying to get something and the van suddenly rolled forwards,” he said.

“She was trying to grab the door and climb in to stop it but she couldn’t. Some men sat on a bench nearby must have seen it heading towards the old man and jumped up, running to it. They were trying to hold it back but the van was rolling him under.”

He added: “The woman officer was mortified.

“I went with another man to look for the jack in the back of her van to try and lift it up. When we found it we were all trying to get it jacked up to take the pressure off him. He was still awake, someone was kneeling down talking to him. Then more police, paramedics and a fire engine arrived and moved us all away. The police took over jacking the van up.

“The place was jam packed and people were crying their eyes out.

“It had all happened in front of them in split seconds.”

The witness, who regularly uses the park with his young son, said: “The police van ended up just inches away from an ice-cream van – if anyone had been queuing it would have got them too.

“It was a terrible freak thing. The ice cream van parks on the slope all the time, vehicles just shouldn’t be allowed in the park.”

Another witness Alison Dowson, who walks her dogs in the park, arrived at the scene just after it had happened.

“The victim had been walking with a zimmer frame. It’s very sad,” she said.

“Some men had tried to push the van back but it was too late.”

Pudsey ward Councillor Mick Coulson (Lab), who is also portfolio holder on Leeds Council for community safety, said he had been horrified to hear what happened, and said that his thoughts were with the victim’s family.

“It was just a sunny Saturday afternoon when everyone should have been enjoying themselves,” he said.

“Pudsey Park is the second most popular park in the whole of Leeds after Roundhay Park.

“We are waiting to find out this man’s identity so we can offer his family support and our wishes.”

A police spokesman said the van had rolled forward and collided with the elderly man who had been walking in the park.

Paramedics were called to the scene but he died of his injuries, the spokesman said.

The incident was immediately referred to the Independent Police Complaints Commission.