North Korea will soon carry out a nuclear experiment, and Iranian scientists could be present at the explosion site, sources who are familiar with the issue told The Jerusalem Post Monday.

Iranian officials from the Shahid Hemmat Industrial Group observed a failed North Korean rocket launch on April 13, according to a report by the South Korean Yonhap news agency.

Although Seoul has neither confirmed nor denied the report, it believes that a delegation of a dozen Iranian scientists may have been technically involved in North Korea´s failed long-range rocket launch, which North Korea said was a satellite launch.

Now, the Islamic Republic may be planning a presence at North Korea´s upcoming third nuclear test as well.

South Korea government sources said on Sunday that North Korea appears to have completed preparations for the test, and would need only to push a button to detonate an atomic bomb.

The test could come as soon as early to middle May.

North Korea has tested two atomic bombs in recent years, once in 2006 and again in 2009 - both times after it carried out failed missile tests.

The North´s nuclear weapons program is mainly based on plutonium, while Iran is mostly relying on uranium in its efforts to build a bomb. Yet some analysts believe that Tehran may be pursuing a parallel secret plutonium nuclear program. Similarly, North Korea is also known to have enriched uranium through spinning centrifuges.

On April 15, North Korea exhibited 3-stage missiles at a military parade, which security analysts said were liquid fuel intermediate range projectiles, putting US territory such as Hawaii or Alaska within target range. While some believed the missiles were mock-ups, US and German defense experts said they believed the exhibitions were closely based on actual missiles in North Korea´s possession.

Iran´s own missile program is based on North Korean missile engines.

The suspected Iranian presence and involvement comes as tensions between the totalitarian North Korea and Seoul have soared. Pyongyang has issued repeated threats this month to carry out "special action" against South Korea and "to annihilate reckless challenges from rebellious elements."

The messages threatened to "raze all sources of provocation to the ground with unprecedented special means and our own methods" within three to four minutes.

"Do they still not understand our determination to retaliate?" an official North Korean website said this week, adding, "revolutionary forces never utter empty words."

South Korea is taking the threats seriously due to the fact that Kim Jong-Un is a new leader and little is known about him. According to assessments by South Korean military experts, an attack could take the form of ´suicide drones´ - unmanned flying vehicles with explosives attached to them, rocket attacks such as those fired at the South last year, or terror attacks on strategic sites such as power plants and water sites. Civilian targets like subway systems could be attacked.

"North Korea’s criticism and threats against South Korea have gone to extremes," wrote Cheon Soengwhun, of the Seoul-based Korean Institute of National Unification, in a recent paper. "It seems that words no longer matter and only actions are left," he added.

Soengwhun stressed that the South Korean public heavily criticized North Korea for pouring some 2 billion dollars - the equivalent of 30 percent of its annual budget - into celebrations of its late leader´s birthday, while its population starves and the country remains impoverished

The paper noted that South Korea´s Ministry of National Defense said it would "adamantly punish North Korea in the case of its provocation."

Last year, North Korea sunk a South Korean naval corvette and shelled an island under South Korea´s control, sparking fears of an all-out war. (© 1995-2011, The Jerusalem Post 05/01/12)