Tulisa Contostavlos drugs trial collapses

Singer and TV star Tulisa Contostavlos's trial over drugs allegations has collapsed.

Judge Alistair McCreath told Southwark Crown Court he believed prosecution witness Mazher Mahmood had lied to the court.

Mr Mahmood claimed that Ms Contostavlos had put him in touch with her rapper friend Mike GLC to supply him with Class A drugs.

Ms Contostavlos, a former X Factor judge, had denied the allegations.

Jon Brain reports.