LUCKNOW, April 7 -- The car blaze in Rampur that claimed the lives of a woman constable and her two-year-old son in February was not an accident but a carefully planned double murder allegedly hatched by her husband, police said after cracking the case 40 days later.

Addressing the media on Monday, Rampur superintendent of police (SP) Somendra Meena said the woman constable's husband, his younger brother and three associates conspired to kill her to allegedly claim insurance and compensation money, while also seeking to remove an obstacle to the husband's alleged relationship with another woman.

Police on Monday arrested Daan Singh, 34, the victim's husband, along with Noor Hasan, 27, and Salman, 26. Daan Singh's brother Ravi Singh, 31,...