A man in his 50s was rushed to hospital with serious injuries after being attacked by a group of "10 to 15 teenagers".

A woman, who does not want to be named, witnessed the "terrible incident" while walking her dog along Elm Road in Thetford at around 7pm on Tuesday.

She recalled how the group approached the man from behind and began "insulting him, kicking him and laughing at him" until he "lost his balance".

One of the group kicked him again and he fell to the ground, unable to get up.

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She explained they wanted to continue hitting him while he was lying on the floor but quickly ran away when they saw her hurrying over.

The woman called 999 and the ambulance service arrived soon after to take the man to West Suffolk Hospital.

"Since I am a religious person, this situation was wild for me," she said.

"I've had never seen anything like it and I imagined being in that position myself.

"This whole situation brought tears and pain to me. I just kept thinking about how cruel children are.

"I feel for the parents who raised children that can be so cruel and disrespectful to another person."

A spokeswoman for Norfolk Constabulary confirmed enquiries are ongoing.