Rupert Grint has lent a touch of Hogwarts magic to the Olympic torch relay, carrying the flame for a leg in northwest London to cheers from hundreds of well-wishers.

Grint, who played Harry Potter's faithful friend Ron Weasley in the popular movie franchise, started his leg of the relay at Middlesex University on Wednesday. He was mobbed as he finished his run.

The 23-year-old actor said that he had not known what to expect, as running was "kind of a new thing" for him, but he was helped by the fact that most of his section was downhill.

The relay ends Friday when the last torchbearer lights the cauldron at the opening ceremony in the Olympic Stadium to mark the official start of the London games.