TV
The first series, starring Freema Agyeman, Jamie Bamber and Bradley Walsh, opened its seven-episode run with strong ratings earlier this year. The second half of the series is yet to air.
Series two will see the return of the original cast and will go into production later this year.
"This new commission brings our total order to 26 episodes, which demonstrates our commitment to series that have concepts and storylines that can run long-term," said ITV's Laura Mackie.
"Audiences clearly loved the first series, which featured the cream of British acting talent with gripping 'torn from the headlines' storylines, and this will again be at the heart of the new series."
Series creator Dick Wolf added: "This is a great day for the Law & Order brand. On the heels of the original Law and Order tying Gunsmoke's all time drama series record of 20 years, and Law and Order: SVU's renewal for season 11, it's wonderful to have pick-ups on both sides of the Atlantic."
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