Apart from the four accused of killing Naresh, a resident of Mukeempur village, the police arrested two others for supplying them arms.
The incident took place on September 2 when the accused fired at Naresh several times.
An FIR was lodged on the complaint of his brother, Devendra, against Ankush, Nitin alias Bholu, Omvir and other unknown persons under Section 302 of the Indian Penal Code, Superintendent of Police (SP) Iraj Raja said.
During investigation, Amit and Vinit were found involved in the incident.
Their names were added in the FIR lodged under the SC/ST Act.
Naresh had borrowed Rs 36,000 from Bholu and later paid back Rs 10,000, police said.
Bholu was pressurising Naresh to pay the pending amount.
They had heated arguments many a time over the issue.
Naresh threatened Bholu, saying he would complain to police.
On September 2, Bholu, who is a member of block development committee of Bhojpur, reached Mukeempur village with his accomplices and called Naresh from someone else’s phone and asked to meet.
When he reached there, they fired at him indiscriminately.
They had bought two pistols for Rs 30,000 each from arm suppliers, named Islamuddin and Fazru, who were later arrested with two country-made pistols of 315 from the fields of Nahali village.
In total, police have arrested six persons and recovered five country-made pistols and eight live cartridges from them, the SP Rural said.