A POLICE officer is swapping chasing criminals for running 26 miles for charity.

Cathryn Greer, aged 41, a detective constable with Greater Manchester Police is pulling on her running shoes and heading to the capital to take part in this year's London Marathon.

The 26-mile run takes place on April 13, when thousands of fitness enthusiasts descend onto the streets of London.

The mother-of-one, from Egerton, said: "I ran the New York Marathon in 2006 and I have since run a few half marathons. But for the London Marathon, I have had to step up my training."

Mrs Greer, whose family will be waiting at the finishing line, hopes to raise more than £1,000 for The Christie Hospital, Manchester.

She said: "My father-in-law died of Hodgkin's Lymphoma in 2004 and was treated at The Christie Hospital so running and raising money for it makes it more personal."

The Flora London Marathon starts near Blackheath, south London and ends at St James's Park.

To sponsor Mrs Greer visit www.justgiving.com/cathryngreer.