File: North Korean vessel Kang Nam I, is seen anchored in Hong Kong waters.
June 18: The South Korean Army Multiple Launch Rocket System fires during a military drill against a possible attack from North Korea.
June 15: Tens of thousands of North Koreans gather at a rally at Kim Il Sung Square in Pyongyang, North Korea.
June 10: South Korean soldiers use binoculars to look at the North side from Imjingak, north of Seoul, South Korea.
June 9: South Korea heavy armored vehicles assemble during a military drill against a possible attack from North Korea in Paju.
Released June 8: North Korean leader Kim Jong Il gestures as he visits the Kosan Fruit Farm.
An undated photo released in January 2009 shows a missile firing drill at an undisclosed location in North Korea.
May 30: South Korean marines man at their positions at the South Korea's western Yeonpyong Island, near the disputed sea border with North Korea.
The recent aborted voyage of a North Korean ship, photographs of massive tunnels and a top secret meeting have raised alarm bells that one of the world's poorest nations may be aspiring to join the nuclear club — with help from its friends in Pyongyang. No one expects military-run Burma, renamed Myanmar, to obtain an atomic bomb anytime soon, but experts have the Southeast Asian nation on their radar screen.
"There's suspicion that something is going on, and increasingly that cooperation with North Korea may have a nuclear undercurrent. We are very much looking into it," says David Albright, president of the Institute for Science and International Security, a Washington, D.C. think tank.
The issue is expected to be discussed, at least on the sidelines, at this week's ASEAN Regional Forum, a major security conference hosted by Thailand. U.S. Secretary of State Hillary Rodham Clinton, along with representatives from North Korea and Burma, will attend.
Alert signals sounded recently when a North Korean freighter, the Kang Nam I, headed toward Burma with undisclosed cargo. Shadowed by the U.S. Navy, it reversed course and returned home earlier this month.
It is still not clear what was aboard. U.S. and South Korean officials suspected artillery and other non-nuclear arms, but one South Korean intelligence expert, citing satellite imagery, says the ship's mission appeared to be related to a Burma nuclear program and also carried Scud-type missiles.
The expert, speaking on condition of anonymity because of the sensitivity of the issue, said North Korea is helping Burma set up uranium- and nuclear-related facilities, echoing similar reports that have long circulated in Burma's exile community and media.
Meanwhile, Japanese police arrested a North Korean and two Japanese nationals last month for allegedly trying to export a magnetic measuring device to Burma that could be used to develop missiles.
And a recent report from Washington-based Radio Free Asia and Burma exile media said senior Burma military officers made a top secret visit late last year to North Korea, where an agreement was concluded for greatly expanding cooperation to modernize Burma's military muscle, including the construction of underground installations. The military pact report has yet to be confirmed.
In June, photographs, video and reports showed as many as 800 tunnels, some of them vast, dug in Burma with North Korean assistance under an operation code-named "Tortoise Shells." The photos were reportedly taken between 2003 and 2006.
Thailand-based author Bertil Lintner is convinced of the authenticity of the photos, which he was the first to obtain. However, the purpose of the tunnel networks, many near the remote capital of Naypyitaw, remains a question mark.
"There is no doubt that the Burmese generals would like to have a bomb so that they could challenge the Americans and the rest of the world," says Lintner, who has written books on both Burma and North Korea. "But they must be decades away from acquiring anything that would even remotely resemble an atomic bomb."
David Mathieson of the New York-based Human Rights Watch, who monitors developments in Burma, says that while there's no firm evidence the generals are pursuing a nuclear weapons capability, "a swirl of circumstantial trends indicates something in the nuclear field is going on that definitely warrants closer scrutiny by the international community."
Albright says some of the suspicion stems from North Korea's nuclear cooperation with Syria, which now possesses a reactor. Syria had first approached the Russians, just as Burma did earlier, but both countries were rejected, so the Syrians turned to Pyongyang — a step Burma may also be taking.
Since the early 2000s, dissidents and defectors from Burma have talked of a "nuclear battalion," an atomic "Ayelar Project" working out of a disguised flour mill and two Pakistani scientists who fled to Burma following the Sept. 11 World Trade Center attack providing assistance. They gave no detailed evidence.
Now a spokesman for the self-styled Burma government-in-exile, the National Coalition Government of the Union of Burma, says that according to sources working with the dissident movement inside the Burma army, there are two heavily guarded buildings under construction "to hold nuclear reactors" in central Burma.
Villagers in the area have been displaced, said spokesman Zinn Lin.
Andrew Selth of Australia's Griffith University, who has monitored Burma's possible nuclear moves for a decade, says none of these reports has been substantiated and calls the issue an "information black hole."
He also says Western governments are cautious in their assessments, remembering the intelligence blunders regarding suspected weapons of mass destruction in Saddam Hussein's Iraq.
A U.S. State Department official, speaking on customary rules of anonymity, said he would not comment on intelligence-related matters such as nuclear proliferation.
"I don't want that to be seen as confirmation one way or the other. Obviously, any time that a country does business with North Korea we're going to watch to see what that is," the official said.
Alarm bells about Burma's aspirations have rung before. In 2007, Russia signed an agreement to establish a nuclear studies center in Burma, build a 10-megawatt nuclear research reactor for peaceful purposes and train several hundred technicians in its operation.
However, Russia's atomic agency Rosatom told The Associated Press recently that "there has been no movement whatsoever on this agreement with Burma ever since."
Even earlier, before the military seized power, Burma sought to develop nuclear energy, sending physicists to the United States and Britain for studies in the 1950s. The military government established a Department of Atomic Energy in 2001 under U Thaung, a known proponent of nuclear technology who currently heads the Ministry of Science and Technology.
Burma is a party to the Nuclear Nonproliferation Treaty, and under a safeguards agreement with the International Atomic Energy Agency, it is obligated to let the U.N. watchdog know at least six months in advance of operating a nuclear facility, agency spokesman Ayhan Evrensel said.
Evrensel said the Vienna-based IAEA has asked Burma to sign a so-called "additional protocol" that would allow agency experts to carry out unannounced inspections and lead to a broader flow of information about Burma's nuclear activities.
The regime has remained silent on whatever its plans may be. A Burma government spokesman did not respond to an e-mail asking about Russian and North Korean involvement in nuclear development.
In a rare comment from inside Burma, Chan Tun, former ambassador to North Korea turned democracy activist, told the Thailand-based Irrawaddy magazine, "To put it plainly: Burma wants to get the technology to develop a nuclear bomb.
"However, I have to say that it is childish of the Burmese generals to dream about acquiring nuclear technology since they can't even provide regular electricity in Burma," the Burma exile publication quoted him last month as saying.
Some experts think the generals may be bluffing.
"I would think that it's quite possible Yangon would like to scare other countries or may feel that talking about developing nuclear technologies will give them more bargaining clout," said Cristina-Astrid Hansell at the California-based James Martin Center for Nonproliferation Studies. "This is not unreasonable, given the payoffs North Korea has gotten for its nuclear program."