FILE - In this March 31, 2014 file photo released by the South Korea Defense Ministry Wednesday, April 2, 2014, an unmanned drone lies on the ground damaged on Baengnyeong Island, South Korea, near the West Sea border with North Korea when the two Koreas fired hundreds of artillery shells into each other's waters. South Korean experts say two small drones believed to have been flown across the border by the North amid rising military tensions were crude and decidedly low-tech - with cameras available on the Internet for hundreds of dollars - but underscore a potential new threat that must be taken seriously. (AP Photo/South Korea Defense Ministry, File )