
The military of South Korea on Thursday confirmed that their key no-fly zone near the presidential office was breached by a North Korean drone in a rare incident of incursion last month, which they had previously denied.Military tensions increased on the Korean peninsula last year as weapons tests were carried out by North Korea every month, which included firing one of the most advanced intercontinental ballistic missiles.
Five drones were then sent by Pyongyang across the border into the airspace of South Korea on December 26 for the first time in five years, which instigated Seoul to scramble jets in response.
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The military of South Korea issued an apology after it failed to shoot down any of North Korea's drones in a five-hour operation, as it said that the drones were "too small".
Reports of infiltration by drones in the crucial no-fly zone, which is called P-73, were repeatedly denied by South Korea's military.
"It is not true that (the North Korean drone) did not pass over Yongsan," a spokesperson for the Joint Chiefs of Staff, Lee Sung-jun on Thursday said, talking about the area of the presidential office and defence ministry's location.
An official of the military said that in an investigation they discovered "the trail of a small drone of the enemy" had crossed the no-fly zone's northern end.
"We make it clear that there is no problem with the safety of the Yongsan office," said the official.
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Last week, the military of South Korea said that the North "could not have obtained meaningful information" by sending drones because of their low technology level.
"It is worrisome that Yongsan, where South Korea's top security control facilities are located, was infiltrated in the height of tension between the two Koreas," said Yang Moo-jin, University of North Korean Studies' professor in Seoul.
He added that public trust will be damaged by their initial denials.
(With inputs from agencies)