A defiant North Korea is threatening both the United States and South Korea in response to the United Nations decision to invoke additional sanctions on Pyongyang for it's rocket launch late last year.
Calling the U.S. a sworn enemy of North Korea, the government of Kim Jong Un vowed to launch more missiles and conduct a nuclear test.
Pentagon correspondent Barbara Starr looks into how dangerous the North's nuclear capability really is.
By Pam Benson
Satellite imagery of a North Korean nuclear test site identifies what could be key installations that would likely play a prominent role if Kim Jong Un orders a test, which the government threatened to do on Thursday.
The analysis of the Pung-gye-Ri Nuclear Test site by U.S.-Korea Institute at Johns Hopkins University’s 38 North blog shows recently completed structures essential to an underground nuclear weapons test.
One is believed to be a command and control bunker. Another photo shows what appears to be a radio relay system that zigzags through a valley, which the 38North analysts believe could be used as part of a communications system linking the bunker to the North Korean leadership in Pyongyang.
"Located about 150 meters (164 yards) north of the test tunnel entrance, the bunker, used only when a test is about to be conducted, would contain equipment for controlling the nuclear device, managing instruments for gathering test data and communicating with authorities in Pyongyang," the report stated. "The bunker would also provide shelter for all personnel in the area."
By Dugald McConnell and Brian Todd
Residents of Washington may be surprised by a helicopter flying low overhead this week, endlessly prowling the city to map its radiation signature.
The helicopter is crisscrossing the city, like a lawn mower covering a lawn, flying as low as just 150 feet off the ground. CNN spotted it northwest of downtown on Monday, flying low over the buildings, back and forth, east to west.
The purpose: to produce a baseline scan of the natural radiological readings in the capital. Once the map is done, any new anomalies - or suspicious radioactive activity - could be more easily detected.
By Barbara Starr
The Syrian regime this week fired at least two Iranian-made, short-range ballistic missiles in what appears to be an effort to more precisely target Syrian rebels, two U.S. military officials tell CNN.
The Fateh A-110 missiles are more accurate than the older Scud variants that Syrian government forces have used in recent weeks.
The U.S. military officials declined to be identified because of the sensitive nature of the information. The Iranian government has not commented on the issue.
The Fateh trades range for accuracy. It can travel about 125 miles, while the Scud can go about 185 miles. But the Fateh has a "circular error probable" or - CEP - of 330 feet, while the Scud's CEP is 1,480 feet. CEP is defined as the radius of a circle in which half of a missile's lethal payload falls and is the standard measure of a missile's accuracy.
Sources tell CNN’s Barbara Starr that the Pentagon and US intelligence services are consulting with Syria's neighbors Turkey, Israel and Jordan about what to do if it looks like Assad is about to launch a chemical attack on his own people.
A senior US official says all the allies are now considering how to keep Syria from putting chemical warheads on its artillery or missiles.
But an airstrike to stop it, could cause havoc if residual chemicals escape.
What if Assad leaves? US officials say they have long been planing for 'the day after Assad" – such as training Jordanian troops to provide security – but for now they just hope Syrians troops will keep those chemical weapons under lock and key.
By Barbara Starr
Syrian forces began combining chemicals that would be used to make deadly sarin gas for use in weapons to attack rebel and civilian populations, a U.S. official tells CNN.
The United States obtained intelligence over the weekend indicating this development, according to the official who had direct knowledge of the latest information.
The intelligence, the official said, came from multiple sources but declined to provide any more details about how the United states learned of it.
Sarin gas, the source said, could most readily be used to fill artillery shells.
Syrian State TV cited a Foreign Ministry official on Monday as saying the country would never use chemical weapons on its own people.
CNN reported on Sunday that U.S. intelligence is concerned about the Syrian government's intent regarding its vast chemical weapons stockpiles after what one senior American official described as "worrying signs" of activity in "the last few days."
By Barbara Starr
U.S. Secretary of State Hillary Clinton warned on Monday the United States was prepared to act if Syria used chemical arms as new concerns surfaced about those weapons, although Syria said it had no intention of using them on its own people.
Speaking after meetings in Prague, Clinton reiterated that such a move by the regime of Syria's Bashar al-Assad would cross a red line previously drawn by President Barack Obama.
"I'm not going to telegraph in any specifics what we would do in the event of credible evidence that the Assad regime has resorted to using chemical weapons against their own people. But suffice it to say, we are certainly planning to take action if that eventuality were to occur," Clinton told reporters.
"There is no doubt that there is a line between even the horrors that they have already inflicted on the Syrian people and moving to what would be an internationally condemned step of utilizing their chemical weapons."
Clinton met with the Czech foreign minister and discussed the concerns, she said after the meeting. Clinton said the Czech Republic has extensive expertise with chemical and biological weapons. FULL POST
Behind every Hellfire missile, there's an actual human being remotely pulling the trigger. But the Pentagon is preparing for the day when robots are capable of targeting and launching a strike on their own.
CNN's Chris Lawrence reports on the Pentagon's new rules on drones, effectively forbidding the development of lethal weapons with no human control.
By Jamie Crawford with reporting from Jill Dougherty, Elise Labott and Pam Benson
The United States is closely watching how rebel forces operate inside Syria, and what their end objectives might be as the Obama administration weighs whether or not to provide arms to the Syrian opposition.
"Will providing arms to the opposition convince the people who support [Syrian President] Bashar al-Assad, in many cases because they are afraid of their own existence, or will it simply lead to more fighting - that is the question that we are considering," Robert Ford, the U.S. ambassador to Syria, said during a panel discussion in Washington on Thursday on the crisis in Syria.
"Arms are not a strategy, arms are a tactic," Ford said about the deliberation the administration is undertaking on the question, and that a "military solution" is not the best path forward for Syria.
"The president has never taken the provision of arms off the table," he said. "And so, as we think about our policy of sending arms or not, and today we do not, we want to make sure that tactic plays into and helps us achieve a strategy of enabling the Syrian people to reach a political solution."
By Pam Benson
Recent satellite photos show continued activity at a controversial Iranian military site that international weapons inspectors have repeatedly been denied access to, according to a Washington-based think tank.
The Institute for Science and International Study obtained imagery from DigitalGlobe taken on November 7 that the institute says shows changes in the roofs on two key buildings at the Parchin Military Complex. ISIS also pointed out there is a new addition on the building suspected of containing a high-explosives chamber and piles of dirt not seen in an image taken on September 19.
ISIS said the imagery indicates additional changes will be made to the site, making it more difficult for the international inspectors.
"The considerable amount of new materials, equipment, and rows of earth piles suggest that further construction will be taking place, thus increasing the level of alteration and further degrading the chance of obtaining reliable environmental samples if and when (International Atomic Energy Agency) inspectors gain access to the site," ISIS stated.
Since January, the IAEA has been seeking access to the site, where it suspects Iran may have conducted high-explosives tests related to the development of nuclear weapons. Iran denies that Parchin has any role in its nuclear program.
The latest IAEA report on Iran released earlier this month said the "extensive activities" at the Parchin site are certain to have "seriously undermined" the agency's verification process.
Those activities include "significant ground scraping and landscaping" with new dirt roads.