Flights Banned Over Boston Marathon Blast Site

BOSTON (CNN) -- As the horror of the explosions near the finish line of the nation's most famous marathon sank in, government officials mobilized to respond on Monday afternoon.

Aviation authorities banned planes from flying over of the site of the explosion, the Federal Aviation Administrion said. The temporary flight restriction came at the request of law enforcement and extends three nautical miles in all directions, up to a height of 3,000 feet, FAA spokeswoman Arlene Salac said.

Attorney General Eric Holder instructed the Justice Department to deploy its "full resources" to the investigation into the blasts that killed at least two people and left dozens injured.

He spoke to the head of the FBI, Robert Mueller, and to the U.S. Attorney for the District of Massachusetts, Carmen Ortiz. Her office is coordinating responses from the Justice Department, the FBI, the Bureau of Alcohol, Tobacco and Firearms and other law enforcement officials.

Homeland Security Secretary Janet Napolitano was briefed, and she ordered her department to provide "whatever assistance is necessary" to state and local authorities, an administration official said.

From CNN Chief White House Correspondent Jessica Yellin, CNN Senior Producer Carol Cratty and CNN Producer Mike Ahlers.

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