The incident happened at around 6pm on Sunday 11 March 2018 on Wimborne Road.
The victim – a 30-year-old Wimborne man – was walking along the pavement close to Pets Corner when he noticed a silver van with an orange light on top, which pulled up next to him.
He didn’t recognise the van so did not take too much notice of it and walked past it. The next thing he knew he was hit in the face with an unknown object, causing him to fall to the ground. He was then kicked in the head, causing him to lose consciousness.
The victim suffered a broken nose and two black eyes.
Police Constable Hannah Loveridge, of Poole police, said: “This was a particularly nasty, unprovoked attack and I have been making a number of enquiries in order to identify those involved.
“I am appealing to anyone who witnessed the incident, or has any information about the individuals involved or the van itself to please contact me.”
Anyone with information is asked to contact Dorset Police at www.dorset.police.uk, via email firstname.lastname@example.org, or by calling 101, quoting occurrence number 55180036984. Alternatively, contact Crimestoppers anonymously on 0800 555111 or via www.crimestoppers-uk.org.