Detectives investigating the unsolved murder of a taxi driver 30 years ago believe someone nearby holds a “crucial piece of evidence.”

Kent Police today re-released a four minute video in its appeal to catch Derek Brann’s killer.

The 48-year-old’s blood-soaked taxi was found abandoned in a layby of a residential area in Sandgate, near Folkestone, on the morning of Sunday 6 November 1988.

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His body was discovered a fortnight later dumped and hidden behind a crash barrier on the M20 motorway.

A post-mortem revealed he had been stabbed multiple times.

Ds Andrea Richards, who has been working on the cold-case, said: “This was a shocking and violent crime and one we remain committed to solving.

"I believe someone out there holds a crucial piece of information that will allow us to bring Derek’s killer to justice.

“For whatever reason they have not come forward yet, but I would urge them to consider the impact this killing has had on the Derek’s family.

“They have had to move on with their lives without him and his children have had to grow up without their father. They deserve to know who took Derek’s life.”

“We will never close the books on an unsolved murder.”

Advances in DNA sequencing could hold the key to catching Mr Brann’s killer, she added.

The cold case was reopened last year when the victim’s sons Aaron and Adrian Brann launched a fresh appeal to find their father’s killer.

Aaron, now 44, was 15 when his father was killed.

He said: “Still to this day I cannot understand why anybody would have done what they did to dad. It’s incomprehensible.

“It’s difficult to live with but you just get on with your life. Since our mum died last January it has brought up all sorts of memories again, and reminded me of the desire we all have to get a positive conclusion to it all.”

Anyone with information about Mr Brann’s death is urged to call 01634 884043 and leave a message for the cold case investigation team or call the anonymous Crimestoppers hotline on 0800 555111.