By Soo-hyang Choi and Hyonhee Shin
SEOUL (Reuters) - A&nbsp;North&nbsp;Korean&nbsp;drone&nbsp;briefly&nbsp;entered&nbsp;a no-fly&nbsp;zone&nbsp;surrounding&nbsp;South&nbsp;Korea's&nbsp;presidential&nbsp;office&nbsp;when&nbsp;it&nbsp;intruded&nbsp;into the&nbsp;South's&nbsp;airspace&nbsp;last&nbsp;week,&nbsp;Seoul's&nbsp;military&nbsp;said&nbsp;on&nbsp;Thursday,&nbsp;fuelling&nbsp;criticism&nbsp;over&nbsp;its&nbsp;air&nbsp;defences.
The&nbsp;drone&nbsp;was among five&nbsp;North&nbsp;Korean&nbsp;drones that crossed into the&nbsp;South&nbsp;on Dec. 26, prompting&nbsp;South&nbsp;Korea's&nbsp;military&nbsp;to scramble fighter jets and helicopters. The&nbsp;military&nbsp;was criticised for failing to bring down the&nbsp;drones which flew&nbsp;over&nbsp;the&nbsp;South&nbsp;for hours.
South&nbsp;Korea's&nbsp;Joint Chiefs of Staff (JCS) had denied that one of the&nbsp;drones&nbsp;intruded&nbsp;into a no-fly&nbsp;zone&nbsp;near President Yoon Suk-yeol's&nbsp;office&nbsp;in Seoul, but on&nbsp;Thursday&nbsp;confirmed it had violated the&nbsp;northern end of the area.
A JCS spokesperson&nbsp;said&nbsp;there was a change in&nbsp;its&nbsp;analysis after an inspection of the&nbsp;military's readiness posture&nbsp;over&nbsp;the latest intrusion.
The JCS&nbsp;said&nbsp;the&nbsp;North's unmanned&nbsp;aircraft did not&nbsp;fly&nbsp;directly&nbsp;over&nbsp;the Yongsan area, where Yoon's&nbsp;office&nbsp;is located.
Yoo Sang-bum, a member of the parliamentary intelligence committee,&nbsp;said&nbsp;the possibility of the&nbsp;drone&nbsp;taking photos of the&nbsp;presidential&nbsp;compound, which also houses the JCS headquarters, could not be ruled out, citing intelligence officials.
North&nbsp;Korea has about 500 unmanned aerial vehicles of 20 different types, most of which measure about one metre to six metres (40 to 236 inches), but which also include a small amount of self-destruct attacker devices, Yoo&nbsp;said.
"A movement of developing medium- and large-sized&nbsp;drones for long-distance reconnaissance has been detected but it appears to be at an early stage, and securing technologies such as high-performance detection sensors would be key," Yoo&nbsp;said&nbsp;after a briefing by the spy agency.
The border crossing has sparked&nbsp;criticism&nbsp;over&nbsp;South&nbsp;Korea's&nbsp;air&nbsp;defences&nbsp;at a time of the&nbsp;North's growing nuclear and missile threats.
The defence ministry has pledged to launch a new&nbsp;drone&nbsp;unit to improve&nbsp;its&nbsp;surveillance and reconnaissance system especially against smaller&nbsp;drones.
It also unveiled plans&nbsp;last&nbsp;week&nbsp;to spend 560 billion won ($441 million)&nbsp;over&nbsp;the next five years to boost&nbsp;its&nbsp;anti-drone&nbsp;capability, including developing&nbsp;airborne laser weapons and signal jammers.
Yoon has warned he would consider suspending a 2018 inter-Korean&nbsp;military&nbsp;pact if the&nbsp;North&nbsp;violates&nbsp;its&nbsp;airspace&nbsp;again.
Reclusive&nbsp;North&nbsp;Korea has pursued missile and nuclear weapons programmes in violation of UN Security Council resolutions.&nbsp;North&nbsp;and&nbsp;South&nbsp;Korea are technically still at war because their 1950-53 conflict ended in a truce, not a peace treaty.
&nbsp;
(Reporting by Soo-hyang Choi. Editing by Gerry Doyle and Nick Macfie)

you might like

North Korea drone entered no-fly zone near Yoon's office, South says