With today's arrest, the number of people apprehended by the probe agency has gone upto eight.
Based on interrogation of Ahmad Hussain and Farkruddin, who were arrested by NIA from Mirzapur yesterday, two more people Anil Pandey and Mohammed Raju were arrested from the same area.
NIA alleged Raju, a resident of Barkachha, had purchased explosives from Pandey, who resides in Allahabad, the sources said.
Five blasts were triggered in the venue of 'Hunkar' rally of Modi and two had gone off outside. Eight people, including a militant of Indian Mujahideen, were killed and over dozens injured.
NIA, which was handed over the case, has been carrying out the probe into the case and with the help Intelligence Bureau, had nabbed Yasin Bhatkal who had named the main culprits behind the incident.
NIA was working closely with the central snooping agency and tracking the mobile details of the arrested accused against whom suspicion increased because of transfer of large sums of money.