It happened on the B3081 near Verwood - he had to be cut free by firefighters.
Boscombe Murder Investigation Continues
Detectives in Bournemouth investigating a murder in the Boscombe area of the town are renewing their appeal for information about a vehicle seen in the area.
The vehicle was seen in Roumelia Lane on two separate occasions around the time of the murder on Wednesday, 25 July 2012.
It is believed to be a large saloon car - possibly a Renault Laguna - and was seen just before and just after the incident, between approximately 2am and 2.30am.
Detective Chief Inspector Kevin Connolly said:
"The timing of these sightings is clearly significant and I desperately need to either implicate or eliminate this vehicle from our investigation.
"I urge anyone with information about this vehicle to come forward."
Detectives are also renewing their appeal for any friends or acquaintances of the victim, Reece James Menzies, to contact police as soon as possible.
DCI Connolly continued:
"The motive for this attack, as I have said before, is still not known. I am sure that someone out there, including friends of Reece, will have information that would help us..
"We urge anyone who knew Reece in any way or visited the address where Reece was staying to come forward.
"We understand that it is worrying for people to take the step to speak to police, but I would like to take the opportunity to reassure members of the public that any information will be treated confidentially."
As a result of a previous appeal, a second vehicle seen in the area of Roumelia Lane has been eliminated from the enquiry.
Witnesses and anyone with information should call Dorset Police in confidence on 101 quoting incident number 25:046. Alternatively, call the free and anonymous Crimestoppers line on 0800 555 111 where mobile phone tariffs may apply
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