Inner Circle by Claire McNab

Detective Inspector Carol Ashton is unaware that her investigation of execution-style murders and the bombing of a small-town police station has put her life in grave danger. The case leads her to the fringes of a mysterious underground group whose members are waging an undeclared war against anyone who does not share their extremist views.

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An investigation into the bizarre execution style murders of two men and the seemingly unconnected bombing of a small town police station places Detective Inspector Carol Ashton directly in the firing line. The case leads her to the fringes of a higly organised, extremist militia group whose members are waging an undeclared war against anyone who does not share their views. Overworked and fighting for stability in her person life, will Carol realise her own danger too late, that even law enforcement may be corrupted by the growing power of Inner Circle?