The accused, Rohit Lamba alias Amit alias Mohit (34), is allegedly a contract killer involved in more than a dozen cases of murder, attempt to murder and robbery, police said. His associate, Ritik Thakur (21), was also arrested. According to police, while investigating an attempt-to-murder case, officers received specific information on June 28 that Rohit and Ritik were hiding in Shakti Nagar Extension.