CONCERNS are growing for a missing teenager who was seen on a train to Southampton.

Police have launched a search for 13-year-old Frankie Catton, who has been missing for more than a week.

The schoolgirl was last seen when she left her home in Garden Close, in West Sussex, with another teenager, at 7.45pm on September 3.

She has friends in Hampshire and officers believe she could be in the county and are urging anyone who has seen her to come forward.

Members of the public confirmed they saw Frankie on a train to Southampton last week and she was then seen on Sunday, in the company of the same girl, going from Southampton to Brighton, and alighting at Barnham.

Frankie is white, of slim build, 5ft 7ins, with very long dark brown hair and brown eyes.

Police say that she will appear a lot older than she is and may tell people she is 15 or 16-years-old.

PC Mark Green said: "Her family, like us, are becoming increasingly concerned for her welfare regardless of the sighting and of contacts there have been from her via social media.

"At present it is understood that she is staying at an unknown address with a young family and is still with the friend she left with on Thursday.

"She uses the railway system and has friends in Hampshire, Worthing and Crawley."

Anyone who has seen Frankie or knows where she may be should contact West Sussex Police on 101.