350 Terrorist Suspects Prevented from Boarding Planes Since 2009

The U.S. government has prevented more than 350 people suspected of ties to al-Qaida and other terrorist groups from boarding U.S.-bound commercial flights since the end of 2009, The Associated Press has learned.
The tighter security rules — imposed after the attempted bombing of an airliner on Christmas 2009 — reveal a security threat that persisted for more than seven years after the Sept. 11, 2001, terrorist attacks.
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After the attempted Christmas attack, the intelligence community took a closer look at the names on the terror watch list and set new standards for adding names. The watch list and no-fly list are constantly reviewed, and names are added and removed each day. There are about 30,000 people on the no-fly list and a companion list for people who must receive extra screening at airports, a counterterrorism official told the AP.
The more expansive terror watch list includes about 450,000 names of people the U.S. intelligence community believes are, or could be, a threat to national security because of terrorist ties. Some of the people on the watch list are still being investigated, and there is not enough information for the government to arrest them. More at AP