THE family of hit-and-run cyclist Jim Fleming today appealed for the “mindless” driver to give themselves up to allow “justice” for his orphaned son.

The children, step-children, brother and sister and ex-wife of Mr Fleming made an emotional appeal in front of television cameras a week after the A413 smash.

They released a photograph of his 10-year-old son William, orphaned after mum Pam died from cervical cancer last year and last Wednesday’s accident.

Police today revealed they are searching for a blue vehicle thought to have struck the 47-year-old from behind on the dual carriageway northbound at Gerrards Cross.

They believe the accident happened at 5.50am – but he was not found until 6.30am.

Step-son Mark Twine, 21, said the family wanted justice for William, who lived with his father in Oakside, Denham.

He said: “He has been through enough this year, losing his mum in August last year. He didn’t need to have his dad taken away from him as well.”

He said he and sister Claire’s lives had been turned “completely upside down”.

He said of the driver: “We understand that, at that time, they may have just panicked and driven off, not thinking straight.

“But they have had a week now to think about their actions. It is never too late.”

Mr Fleming’s first wife, Sharron Howard, said her three grown-up children with Mr Fleming had been devastated by his death.

Two of his children, James Howard, 21 and Catriona Stockwell, 25, accompanied her from Hampshire.

Yet she said: “While it is tragic for them, they are old enough to look after themselves, William isn’t.

“Whoever is responsible for this I think is very heartless and mindless if they can just walk away from what they’ve done.”

She said the family “can’t lay Jim to rest, even if we bury him” until the driver is brought to justice.

Ms Howard said: “I don’t think for one minute they could even turn round and say “well, I didn’t know that I hit that person”.”

She said: “They should admit what they have done and face the consequences.”

Elspeth Colburn, one of Mr Fleming’s three siblings, said: “It seems such a heartless act, to drive off from the scene.

“They would have known what happened. Jim was visible.”

Brother Duncan Fleming, from Denham, said paid tribute to his “best mate”.

He said: “He tried to work hard for his family. He lost his wife to cancer back in August, now he’s gone so his 10-year-old son is an orphan.

“So I appeal to anyone out there who has any information, no matter how small or minor, would they please let the police know.”

Supt Mick Doyle appealed to anyone who knew someone who had a blue vehicle that was damaged last week and was perhaps not using it.

He also appealed to garages for information about customers getting work done or seeking quotes on blues vehicles with damage to the front.

Supt Doyle said: “If you were the driver on that morning, come forward now.

“We can’t bring Jim back, we can’t replace Jim for his family or for William but we can get justice.”

Sgt Doyle revisits the scene of the accident:

Police also want to speak to three Polish men who stopped at the scene to assist, but then left before giving officers their details.

Officers carried out stop checks on the road from 5am in the hope that drivers can provide more information about the accident.

Mr Fleming was due to finish his job as a haywarden for Chalfont St Peter Parish Council on Friday to look after William.

The crash happened on the northbound section of the road between the M25 road bridge and the viaduct on the dual carriageway.

An incident room has been set up at Gerrards Cross to deal with the case.

Anyone with information can call Thames Valley Police on 0845 8 505 505 and quote URN 92634 or Crimestoppers anonymously on 0800 555 111.