At least two persons were killed and two injured when suspected Maoist guerrillas started indiscriminate firing in Jharkhand's Giridih district, the state police said on Monday.According to police sources, around 10-15 Maoist guerrillas attacked the house of village head Prabhawati Devi in Bhelwaghati of Giridih district on Sunday night.In the gunfire, Subhash Agrawal and Shayam Sundar were killed on the spot, while Gauri Shanar Agrawal, husband of the village head, and the second son of Ranjit Barnawal were injured in the firing.The injured persons have been admitted in a local hospital.In 2005, Maoist guerrillas killed 17 persons in the Bhelwaghati village.The reason of the killing is not yet clear.Maoist guerrillas are active in 18 of the 24 districts of the state.