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VIENNA, Feb 12 (Reuters) - An international nuclear test monitoring agency said on Tuesday that it had detected an "unusual seismic event" in North Korea, following weeks of speculation that a nuclear test was imminent in the country.
"We have detected an unusual seismic event in North Korea," said Annika Thunborg, a spokeswoman for the Comprehensive Nuclear-Test Ban Treaty Organization, an agency set up to monitor compliance with a ban on nuclear tests that has yet to come into effect.
The Vienna-based CTBTO said on Twitter that "our analysts are currently studying data."
The CTBTO is the world's independent body for monitoring possible breaches of the test ban, with more than 270 facilities established worldwide to pick up signs of any nuclear explosions.
Its stations use different kinds of technology to detect seismic indications as well as radioactive particles in the atmosphere. (Reporting by Fredrik Dahl; Editing by Eric Beech and Mohammad Zargham)