SEOUL: North Korea claimed Saturday it had tested another underwater nuclear attack drone, in its latest response to South Korean and United States military drills, though analysts have questioned whether Pyongyang has such a weapon.

In recent weeks, North Korea has tested what state media have described as an underwater nuclear-capable drone, and also carried out the launch of an intercontinental ballistic missile.
鈥淎 national defense science research institute in the DPRK carried out a test of underwater strategic weapon system from April 4 to 7,鈥� the official Korean Central News Agency said.
鈥淭he underwater nuclear attack drone 鈥楬aeil-2鈥�... cruised 1,000 km of simulated underwater distance ... for 71 hours and 6 minutes.鈥�
KCNA added that 鈥渢he test warhead accurately detonated underwater. The test perfectly proved the reliability of the underwater strategic weapon system and its fatal attack ability.鈥�
North Korea has claimed to have conducted three tests of underwater drones in less than three weeks so far.
On March 23, it claimed to have conducted the first test of the Haeil, which means tsunami in Korean, able to unleash a 鈥渞adioactive tsunami鈥� as it blamed US-South Korea exercises for a deteriorating regional security situation.
Five days later it said it had carried out a second test.
In response South Korean Defense Minister Lee Jong-sup told MPs Seoul was 鈥渃apable of monitoring and detecting such drones infiltrating underwater.鈥�
Satellite imagery has also indicated a high level of activity at North Korea鈥檚 main nuclear complex after leader Kim Jong Un ordered the production of weapons-grade nuclear material be ramped up.
North Korea last year declared itself an 鈥渋rreversible鈥� nuclear power and Kim recently called for an 鈥渆xponential鈥� increase in weapons production, including tactical nuclear weapons.
South Korea and the United States on Wednesday staged joint air drills involving at least one US nuclear-capable B-52H strategic bomber, Seoul鈥檚 military said.
North Korea views such exercises as rehearsals for invasion, and has responded to other recent drills with a spate of increasingly provocative banned weapons tests.
North Korea is seeking to diversify its delivery mechanisms in addition to increasing its nuclear stockpile.
Russia has also reportedly developed a similar weapon 鈥� nuclear-capable Poseidon torpedoes 鈥� but mastering the complex technology required for such weaponry might yet be beyond North Korea, experts said.
But the North鈥檚 claims about the tests should not be 鈥渆asily dismissed for being exaggerated,鈥� Choi Gi-il, professor of military studies at Sangji University, told AFP.
鈥淲hile the North could have exaggerated the degree of success to some extent, they appear to show Pyongyang鈥檚 underlying confidence in this technology, some of which could have been transferred from Russia.鈥�
Russia and North Korea have not officially commented on the transfer of the underwater drone technology, Choi added.