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STORY: U.S. President Barack Obama on Thursday spoke at a memorial service for victims of the Boston Marathon bombing amid a manhunt for suspects seen on video taken before two blasts struck near the finish line on Monday.
He told the gathering that those who chose to intimidate Americans '"picked the wrong city."
Obama is also due to meet families of victims of the bombing and first responders while in Boston, a White House spokesman told reporters aboard Air Force One.
