Police investigating the death of a 13-year-old boy killed in a hit-and-run crash last summer are still trying to track down key witnesses who stopped to help him.

Alfie Brown was on his bicycle when he was knocked down by a Ford Ranger truck on The Street, in Swafield, near North Walsham, on August 10. He died at the scene.

The driver of the Ford, a man in his 50s, initially drove off but was later arrested on suspicion of causing death by dangerous driving.

Eastern Daily Press: The incident happened in The Street in SwafieldThe incident happened in The Street in Swafield (Image: Adam Barker)

Police are still investigating the crash and have issued a fresh appeal for witnesses to come forward, including those who tried to save Alfie as he lay injured.

Detective Inspector Dave McCormack said: "We believe there are other people who stopped to help the victim and who left before emergency services arrived that have not been spoken to by police and who may hold important information.

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“There will also be people travelling either on foot or in a vehicle that may have seen something relevant to the investigation and we strongly encourage them to come forward and speak to us if they have not done so already."

Anybody who was on the B1145 between Knapton and Swafield between 6pm and 6.30pm that evening is asked to come forward with any information, "however insignificant it might seem".

Eastern Daily Press: Locals were left devastated by the shock death of Alfie BrownLocals were left devastated by the shock death of Alfie Brown (Image: Supplied by Alfie's family)

A funeral was held for Alfie at St Nicholas Church in North Walsham on September 4 after more than £15,000 was raised in a crowdfunding campaign. 

Alfie's mother, Rebecca Beauchamp, described him as "beautiful, cheeky boy", with an "ability to make people laugh and feel comfortable". 

His father, Andrew Brown, said: "I miss him and I love him. I wish I could see him one more time."