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CNN's Barbara Starr reports on the evidence the U.S. says it has that implicates Russia in the MH17 plane crash.
CNN's Barbara Starr reports on new intelligence that may help officials uncover what really happened to flight MH-17.
Rocket salvos fired from Gaza, now a daily occurrence in many Israeli cities, are reaching targets deep in Israel.
The Pentagon will send a total of 800 troops to Iraq to help the country combat ISIS. CNN's Barbara Starr reports.
CNN's Barbara Starr looks at some of the contingency plans that may be used if the U.S. military faces danger in Iraq.
As the fight for Iraq continues, the U.S. is evaluating its military options. CNN Pentagon Correspondent Barbara Starr reports.
As the world's most brutal terror group rampages across Iraq, seizing more cities along the way, the U.S. weighs what options it has to stop the violent spree and prevent the Islamic State of Iraq and Syria from establishing its own territory. CNN's Barbara Starr looks at the options.
CNN's Barbara Starr reports on Defense Secretary Chuck Hagel's fiery meeting with a House Committee.
There are new reports that some of America's most critical and well-protected sites may be even more at risk of a devastating attack than we realized - by terrorists, deranged gunmen or hackers.
CNN has learned of three startling new reports that expose serious security problems affecting power and water supplies, federal buildings and nuclear missiles bases - the three most important public sectors that many officials warned were vulnerable to attack in the earliest days after the September 11th attacks.
Shocking nuclear missile security failure
First, at a nuclear missile site, security forces struggled to respond to a "terrorist infiltration" in a scheduled test and ended up failing miserably, according to an internal investigation. As CNN Pentagon Correspondent Barbara Starr discovered, the report found that the Air Force team may not have been able "to prevent theft, damage, sabotage, destruction or detonation of a nuclear weapon."
Federal buildings may be exposed
Elsewhere, a new investigation into security at federal government buildings says that guards haven't received proper training, especially to handle a shooting rampage. After a handful of such incidents, including last fall's shooting at the Washington Navy Yard, there are new concerns that federal offices and their employees are more vulnerable than previously thought.
As CNN Justice Correspondent Pamela Brown reports, millions of taxpayer dollars are spent each year paying companies to supply the more than 13,000 contract security guards - and many lack even the most basic skills needed.
Public utility's control system hacked
CNN has also learned that hackers recently broke into the computer network of a public utility somewhere in the United States. While officials will not release any more information, experts say it could have been a water-treatment plant, a gas pipeline or a power station.
Security experts tells CNN's Brian Todd that America's enemies have mapped its infrastructure for cyber-attack, and that rival governments and terrorist groups could have the capability to strike.
CNN's Barbara Starr reports on three separate strategies that al Qaeda is using to target Europe and the United States.