The reward for information into the crash that killed teenager Jade Clark has been increased to £15,000.
The 16 year old died following a collision on the westbound carriageway of the A31, near the Ashley Heath roundabout, on Sunday February 24th, at 8.20pm.
Police are searching for a Volvo XC90 that fled the scene.
Businesses in the area have have come together to offer the reward, up from £5,000.
Insp Matt Butler said: "The continued support of the local community shows just how much the news of Jade's death has affected people all over the country.
"Jade's family have been totally devastated by their loss, understandably, but the manner of their loss makes it so much worse.
"Therefore it is essential that, for the family, we find the Volvo XC90 to try and give them some peace."
Witnesses and anyone with information should call Dorset Police on 101 quoting incident number 24:393. Alternatively, call the free and anonymous Crimestoppers line on 0800 555111.