NORTH Korea plans to acquire machinery for a biological weapons program - including factories to produce deadly microbes and labs that specialise in genetic modification, according to a report.
The country also has sent scientists abroad to earn advanced degrees in microbiology, and is offering to sell biotechnology services to developing nations, US and Asian intelligence officials and weapons experts told the Washington Post.
Current and former US officials said they have not yet seen any hard evidence that North Korea has ordered the production of any weapons besides samples and prototypes, the paper reported.
"That the North Koreans have (biological) agents is known, by various means," a senior US official familiar with military preparations for a biological attack told the paper on the condition of anonymity.
"The lingering question is, why have they acquired the materials and developed the science, but not yet produced weapons?"
The North's push on the biological front has alarmed US analysts, who say Pyongyang - which is seeking to develop a nuclear warhead capable of reaching the US mainland - could quickly launch industrial-scale production of deadly pathogens with which to threaten its neighbours or US troops.
US officials acknowledge that spy agencies may not be able to detect a change in North Korea's program because the new technologies are ensconced in civilian factories that ostensibly produce agricultural and pharmaceutical products.
"If it started tomorrow, we might not know it unless we're lucky enough to have an informant who happens to be in just the right place," the senior official said.
The US has been aware of North Korea's secret work on a biological weapon as far back as five months before its first nuclear test in 2006, according to the paper.
US intelligence officials sent a report to Congress warning that the communist regimen, which had acquired pathogens that cause smallpox and anthrax, had assembled teams of scientists - but that they lacked some technical skills.
"Pyongyang's resources presently include a rudimentary biotechnology infrastructure," according to the report by the director of national intelligence.
In June 2015, President Kim Jong Un gave a tantalising look at the Pyongyang Biotechnical Institute, a large facility on the grounds of what used to be a vitamin factory. State media described the institute as a factory for making biological pesticides for agricultural use.
But US analysts were alarmed by images that showed industrial-scale fermenters used for growing large quantities of live microbes and dryers that could turn bacterial spores into a fine powder for easy dispersal.
"It is hard to avoid the conclusion that the institute is intended to produce military-size batches of anthrax," North Korea specialist Melissa Hanham wrote in a blog post after the video was shown.
"Regardless of whether the equipment is being used to produce anthrax today, it could be in the near future."
This article originally appeared on The New York Post and has been republished here with permission.