A 15-year-old boy, along with two others, has been arrested for allegedly kidnapping and murdering his 12-year-old cousin in Jharkhand's Hazaribag district, a senior police officer said.

According to Hazaribag Superintendent of Police (SP) Manoj Ratan Chothe, the 12-year-old boy was allegedly kidnapped on March 1 by his teenage brother for ransom.