Thames Valley and Chiltern Air Ambulance was called to Shotover Hill after a woman crashed her sledge into a tree.

The woman, in her early 40s, was airlifted to John Radcliffe Hospital with suspected fractures to her pelvis at about 3.30pm on Saturday.

Meanwhile, police urged people not to try walking on the frozen Oxford Canal by Castle Quay Shopping Centre. Children have been seen in the middle of the canal and officers have been called out several times as people attemped to walk on the ice.

PC Paul Froggatt said: “I can’t emphasise enough how dangerous this sort of activity is. No matter how solid the ice might look, do not even take a chance.”