North Korea may have developed a “super-EMP” weapon capable of emitting more gamma radiation than a 25-megaton nuclear weapon, a former CIA nuclear weapons analyst was quoted as saying by a U.S.-funded radio station Friday.

Peter Vincent Pry told the Voice of America that a group of Russian nuclear weapons scientists approached him in 2004 to warn the U.S. that the technology to make the electromagnetic-pulse weapon had been leaked to North Korea.

While Pyongyang’s nuclear tests in 2006 and 2009 have been dismissed as failures by some analysts because of their low explosive yield, the U.S. expert said they were actually the “signature” of the Russian-designed super-EMP, which could disable the electric power grid across most of the United States.

The now-defunct Soviet Union had conducted an atmospheric test of an EMP weapon in 1962 over Kazakhstan, whose pulse wave set on fire a power station 300 kilometers away and destroyed it within 10 seconds.

Such a weapon ― equal to a massive solar flare such as the “solar maxima” predicted by NASA to occur in 2012 ― poses substantial risk to equipment and operation of a nation’s power grid, and under extreme conditions could result in major long-term electrical outages, U.S. experts have warned.

By Shin Hae-in (hayney@heraldcorp.com)