Police probe One Direction fan's knife photo

Police have launched a probe after a One Direction fan terrorised Harry Styles' ex-girlfriend by sending her a photograph of a woman wielding a knife.

British TV presenter Caroline Flack hit headlines last year (11) when she enjoyed a short-lived romance with the singer when he was 17 and she was aged 32.

Flack was subjected to a barrage of abuse on Twitter.com from envious fans of the boy band, and now she has called in cops after she was sent a photo of a woman clutching a huge knife.

The account from which the picture was sent has since been deleted.

A pal of Flack's tells British newspaper The Sun, "Caroline was shocked."