A professional songwriter is suing pop stars Sam Smith and Eliza Doolittle, alleging they used her lyrics in their chart hits.

Katie Farrah Sopher claims an ex-boyfriend stole her songbook and sold it on to music industry contacts, and the words have since been used in tracks featuring Smith and Doolittle.

She alleges three hits by British electronic duo Disclosure, including Latch which featured Smith on vocals and You & Me, with Doolittle, contain her lyrics.

She is also suing dance duo AlunaGeorge for their contribution to Disclosure's White Noise.

In documents obtained by British newspaper The Mail on Sunday, Sopher is seeking more than $320,000 (£200,000) in damages.