WASHINGTON -- President Obama has called officials in Boston to offer “whatever assistance is necessary” to investigate and respond to the deadly bomb blasts Monday and plans to speak publicly on the incident this evening, a senior White House official said.
Shortly after hearing of the bombs just minutes after they went off, Obama called the Boston mayor and Massachusetts governor to express his concern for the injured to “make clear that his administration is ready to provide needed support,” the official said.
The Secret Service blocked off streets around the White House as details began to emerge. "Out of an abundance of caution, we have expanded our security perimeter at the White House complex,” Secret Service spokesman Ed Donovan said. “It is not unusual to expand or contract these security perimeters."
PHOTOS: Explosions at Boston Marathon
Washington Metro Transit Police ordered day-shift officers to stay on duty “out of an abundance of caution” despite the lack of any “specific or credible threat.”
Boston police said two bombs went off shortly before 3 p.m. along the race route, killing at least two people and injuring many more. A third bomb exploded later at the John F. Kennedy Library.
As news of the explosions broke, Vice President Joe Biden was on a telephone conference call with reporters, apparently learning of the incident as it happened.
Biden interrupted his remarks on gun control after an aide turned on the television.
“Apparently there has been a bombing,” Biden said. “I don’t know any of the details of what caused it,” he said. “Our prayers are with those people in Boston.”
VIDEO: Boston marathon explosion
Shortly after the Boston blast, Pennsylvania Avenue in front of the White House was closed to pedestrians and marked off with yellow police tape.
Meanwhile, the president received briefings from FBI Director Robert Mueller and DHS Secretary Janet Napolitano on the active investigation and response to the incident in Boston, including the ongoing coordination with state and local officials.
Wes Venteicher in Washington contributed to this report
FULL COVERAGE: Boston Marathon attack
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