(CNN) -- North Korea has slammed a South Korean investigation that found that Pyongyang had flown small drones over the border to take photos of strategic sites.
The South Korean findings, released last week, are a "charade for confrontation," the North's Korean People's Army said in a statement reported by state media Monday.
The statement suggested that the South Korean government was "floating the fiction" about the drones' origin "in a foolish bid" to divert public attention away from the Sewol ferry disaster.
Officials in Seoul say the three tiny, unmanned aircraft were found in March and April on the ground in South Korean territory near the heavily militarized border with the North.
Analysis of the drones turned up a "smoking gun" that all three had been sent by North Korea and were set up to return there, the South Korean Defense Ministry said last week.
The small, single-engine propeller planes carried Japanese-made digital cameras and looked as though they could have come from a hobby shop.
All three aircraft were programmed to fly over military facilities, and two of them had images of targets of military interest -- strategically important islands near the demilitarized zone, and the Blue House, the residence and office of South Korean President Park Geun-hye.
The United States, which assisted with the investigation into the drones, wasn't spared North Korea's ire.
Washington is trying to create pretexts "for justifying the huge armed buildup needed for laying a siege to Eurasia and its permanent presence in South Korea," the North's military said in its statement.
But Kim Min-seok, a spokesman for the South Korean Defense Ministry, was unimpressed by North Korea's denials, saying Monday that Pyongyang was "evading responsibility and making excuses."
He went on to criticize North Korea more generally, saying the isolated country "must disappear quickly."
The verbal jousting over the drones comes amid broader tensions on the Korean Peninsula.
Pyongyang has threatened to conduct a new nuclear test, a move that would defy U.S.-led pressure for North Korea to abandon its nuclear program.
Irked by annual U.S.-South Korean military drills in March and April, the North also carried out a series of missile and rocket tests that drew condemnation from the United Nations.
Journalist Stella Kim contributed to this report.