Nuclear
North Korea's nuclear infrastructure started taking shape in the 1950’s with North Korea conducting research radioactive isotopes for use in industry, agriculture, and medicine at the newly established Academy of Sciences (1952). Then in 1961, the DPRK began construction of the Yŏngbyŏn-kun nuclear energy research complex and completed it in 1964. The Soviet Union provided a small research reactor at the site in 1965, and Pyongyang subsequently expanded the complex and built a number of new facilities, including a large plutonium reprocessing plant (Radiochemistry Laboratory). North Korea signed the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) in 1985 but did not submit to International Atomic Energy Agency (IAEA) inspections until May 1992. On October 21, 1994, the United States and North Korea signed the Agreed Framework in which the DPRK agreed to freeze its nuclear program and allow IAEA inspections. In return, the U.S., Japan, and South Korea would provide North Korea with a light-water power plant and heavy oil to replace energy lost by loss of its graphite reactor. However, discrepancies between North Korean declarations and IAEA inspection findings indicate that North Korea might have reprocessed enough plutonium for one or two nuclear weapons. A December 2001 National Intelligence Council report, ascertained that in the mid-1990s that North Korea had produced one, possibly two, nuclear weapons. In mid-2002, U.S. intelligence discovered that North Korea had been receiving materials from Pakistan for a uranium enrichment facility in violation of the NPT and the Agreed Framework.

With the terms of the 1994 Agreement unmet by either side, in December 2002, Pyongyang lifted the freeze on its plutonium-based nuclear weapons program and expelled IAEA inspectors. On 10 January 2003, North Korea declared its withdrawal from the NPT and on 10 February 2005, North Korea announced that it had manufactured nuclear weapons. On 19 September 2005, the North Korean delegation to the Six-Party Talks in Beijing signed a "Statement of Principles" whereby Pyongyang agreed to abandon all nuclear programs and return to the NPT and restore IAEA safeguards in exchange for a U.S.-provided light-water reactor. Implementation has been delayed because North Korea and the United States have desired the other side fulfill its obligations under the agreement first. 

On 9 October 2006, North Korea tested its first nuclear device at 10:35AM (local time) at Mount Mant’ap near P’unggye-ri, Kilchu-kun, North Hamgyŏng Province. In reaction, the UN Security Council placed sanctions on North Korea, Resolution 1718. The U.S. also froze Macao-based Banco Delta Asia assets earlier in September of 2005.  The reasons are controversial, with the U.S. claiming it was a money laundering issue unrelated to the nuclear issue, while experts on North Korea claiming it was to gain negotiating leverage over North Korea’s nuclear weapons program. With Beijing’s behind the scenes negotiations, North Korea returned to the Six-Party Talks. And on 13 February 2007, in the most successful round of the Six-Party Talks, North Korea agreed to an “Action Plan” based on the 2005 “Statement of Principles.” Under the deal North Korea would shutdown its nuclear facilities at Yŏngbyŏn within 60 days in exchange for 50,000 tons of heavy-fuel aid. Separate bilateral talks with the United States and Japan would also begin in order to normalize relations. Furthermore in the Action Plans’ second phase, if North Korea dismantles all of its nuclear weapons program, another 950,000 tons of heavy fuel oil would be delivered along with other humanitarian, economic, and energy aid. On 19 March 2007, assets on Banco Delta Asia were lifted and on 14 July North Korea re-admitting IAEA inspections. The IAEA verified that indeed the Yŏngbyŏn nuclear facility had been shut down.

Biological
Although Pyongyang acceded to the Biological and Toxin Weapons Convention (BWC) in 1987, North Korea is suspected of having a biological weapons program. Reports indicate that North Korea apparently began to produce biological weapons in the early 1980s. To date, North Korea has likely developed and produced anthrax bacteria, botulinum toxin, and plague bacteria. While shrouded in secrecy, North Korea perhaps has between 10 and 20 bioweapons research and development facilities.
 
North Korea's biological weapons profile

Chemical
North Korea's chemical weapons production capability is estimated to be about 4,500 tons per year, and Pyongyang appears to have emphasized the weaponization of mustard, phosgene, sarin, and V-type chemical agents. Reports indicate that North Korea has some 12 facilities where raw chemicals, precursors, and actual agents are produced and/or stored, and six major storage depots for chemical weapons ordnance. Pyongyang also has placed thousands of artillery systems—including multiple launch rocket systems that are particularly effective for chemical weapons delivery—within reach of the Demilitarized Zone (DMZ) and Seoul. North Korea has not signed the Chemical Weapons Convention (CWC).
 
North Korea's chemical weapons profile

Missile
North Korea began its missile development program in the 1970s and tested an "indigenous" Scud-B ballistic missile in April 1984. In its short-range arsenal, Pyongyang has produced the 500km-range Scud-C, the 800km-range Scud-D, and the KN-02 which is an upgraded version of the Russian SS-21 “Scarab” with slightly longer range, about 100 to 120km.

In its medium and intermediate-range arsenal, North Korea has the 1300km-range missile known as the Nodong which it initially tested in1993 (500km) and again in 2006. North Korea has deployed about 175-200 Nodong missiles. In August 1998, North Korea flight-tested the two-stage Paektusan-1 (Taepodong-1), a 1800km range missile, in a failed attempt to place a small satellite into earth orbit. In its second stage, it flew over the main Japanese island of Honshu and landed in the Pacific Ocean after traveling 1,380 km. 

North Korea has also tested anti-ship cruise missiles in 1994, 1997, 2003, and 2007. The first three were based on the CSSC-3 'Seersucker' and identified as the AG-1. The latest anti-ship cruise missile tests on 25 May and 7 June 2007 are believed to have been either the KN-01 or Chinese-made CSSC-3 ‘Seersucker’.

In its long-range missile arsenal, North Korea tested the Paektusan-2 (Taepodong-2) with a range of 4-6,000 km on 5 July 2006. The Paektusan-2 potentially has inter-continental range, but it failed after about 40 seconds of flight. This test broke Pyongyang’s 1999 moratorium on long-range missile tests. It also poses a direct threat to the United States as it has the potential to reach the continental U.S.

In missile sales, United States and Spanish naval forces intercepted a North Korean ship in December 2002 loaded with Scud missiles, but then allowed the ship to proceed to deliver the missiles to Yemen. And in late January 2004, North Korea and Nigeria reportedly agreed to a missile deal, but Nigeria backed out of the agreement in early February under U.S. pressure.  North Korea has exported missiles, missile components, and technology to Egypt, Iran, Libya, Pakistan, Syria, and Yemen.

North Korea is not a member of the Missile Technology Control Regime (MTCR).