The war began when two British customs officers were killed by tribesmen.[3] The First Black Mountain Expedition according to contemporary sources revealed the cause of the seemingly systematic nature of the revolt, as the British first discovered the Hindustani (Ahl-i Hadith) fanatics, who had caused the failure of the negotiations between the locals and the authorities. The campaign made it necessary for another expedition to subdue the colony of the Hindustanis in 1853.[4]
