A 14-year-old boy had both legs broken by a hit-and-run driver.
The Netherton youngster was hit by a van on Huddersfield Road, near its junction with Thong Lane, at 7.45pm last Thursday, but police have only just released details.
A spokesman said: "The van we need to trace is a white Ford Transit with a higher than usual roof. The front nearside lights and bonnet will be damaged. We would like to hear from anyone who may know who the driver is or has repaired a damaged vehicle like this."
Phone Pc Dave Briggs at Huddersfield traffic police on 01484 436847.
