A 44-year-old man was killed and a 16-year-old boy was injured in two separate quad bike crashes in Greater Manchester, police have said.
David Statham, of Staring Way, Rochdale died of a head injury after falling off his quad bike when he hit a kerb in Oldham Road, Manchester, on Saturday.
Police believe the teenager was injured when he crashed into rugby posts at Hollingworth High School, Milnrow.
The boy is being treated in Rochdale Infirmary for a fractured pelvis.
The quad bike had been taken away by the time police arrived at the rugby pitch and officers said they need to trace the owner.
It is believed the bike is owned by another 16-year-old from the Rochdale area.
Anyone with information about Sunday's collision or the whereabouts of the bike owner, should contact Greater Manchester Police.