SEOUL (Reuters) - South Korea warned North Korea on Friday to stop disrupting GPS signal reception which it said forced some fishing boats to return to port and vowed to take action if it continued amid heightened tension over the North’s nuclear and rocket tests.
The South said that it had traced signals that disrupted Global Positioning Satellite reception in the South to four regions in the North close to the rivals’ armed border on Thursday and again on Friday.
South Korea has been on high alert against possible cyber attacks from the North, after its angry rhetoric threatening war and further weapons tests in response to new sanctions imposed last month by the U.N. Security Council and the South.
“The disruptive activity is clearly a flagrant act of provocation that violates the armistice and International Telecommunication Union (ITU) rules and we urge that it stop immediately,” the South’s defence ministry said in a statement.
ITU is the U.N. agency overseeing global telecommunication networks and technologies.
The North would pay a price if it continued, the South’s defence ministry said without elaborating.
The reclusive North and rich, democratic South are technically still at war since their 1950-53 conflict ended in the armistice, not a peace treaty.
The South’s presidential office said the National Security Council met to discuss the GPS disruption and demanded the North “immediately stop the dangerous and reckless activity”.
Hundreds of South Korean fishing vessels off both coasts including 70 of the 332 that had left the eastern port of Sokcho on Friday returned early after suffering GPS malfunctions, media reports said, citing the coast guard.
There have been no reports of air traffic disruptions, the South’s transport ministry said.
The North has attempted similar disruption in recent weeks, officials said.
In March, South Korea’s spy agency said the North had stepped up cyber attack efforts against the South, including a bid to break into a subway control system that was foiled.
South Korea has previously blamed the North for cyber attacks against its nuclear power operator.
The United States accused the North of a cyber attack against Sony Pictures in 2014, forcing the studio to cancel the scheduled release of a comedy film based on the fictional assassination of the country’s leader.
The North has denied responsibility.
Reporting by Ju-min Park and Hooyeon Kim; Editing by Jack Kim and Nick Macfie