SEOUL -- Two civilian suspects were summoned for questioning on Tuesday over allegations of the Republic of Korea (ROK)'s unauthorized civilian drone flights into the Democratic People's Republic of Korea (DPRK), according to local media reports.

The civilians were currently under investigation by a joint military-police task force on allegations of manufacturing and sending drones across the inter-Korean border into the DPRK territory.

One of them was a graduate student in his 30s who claimed in a media interview earlier this month that he had flown drones into the DPRK three times to check radiation contamination near a DPRK uranium plant.

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The other was a director of a drone manufacturing company who faced the first summons.

The task force currently booked and investigated three suspects, including the two as well as the chief executive of the drone manufacturer, on charges of flying drones without authorization and filming domestic military facilities using drones.

All the suspects had been prohibited from leaving the country.

The task force was verifying allegations that the civilians received funds from the defense intelligence command.