BOSTON — Two bombs exploded in the packed streets near the finish line of the Boston Marathon on Monday, killing two people and injuring more than 80 in a terrifying scene of shattered glass, billowing smoke, bloodstained pavement and severed limbs, authorities said.
A senior U.S. intelligence official said two other explosive devices were found near the end of the 26.2-mile course.
At the White House, President Barack Obama vowed that those responsible will "feel the full weight of justice."
There was no word on the motive or who may have launched the attack, and police said no suspect was in custody. Authorities in Washington said there was no immediate claim of responsibility.
"They just started bringing people in with no limbs," said runner Tim Davey, of Richmond, Va. He said he and his wife, Lisa, tried to keep their children's eyes shielded from the gruesome scene inside a medical tent that had been set up to care for fatigued runners, but "they saw a lot."
"They just kept filling up with more and more casualties," Lisa Davey said. "Most everybody was conscious. They were very dazed."
The twin blasts at the race took place almost simultaneously and about 100 yards apart, tearing limbs off numerous people, knocking spectators and at least one runner off their feet, shattering windows and sending smoke rising over the street.
Some 23,000 runners took part in the race, one of the world's oldest and most prestigious marathons. One of Boston's biggest annual events, the race winds up near Copley Square, not far from the landmark Prudential Center and the Boston Public Library. It is held on Patriots Day, which commemorates the first battles of the American Revolution, at Concord and Lexington in 1775.
Boston Police Commissioner Edward Davis asked people to stay indoors or go back to their hotel rooms and avoid crowds as bomb squads methodically checked parcels and bags left along the race route. He said investigators didn't know whether the bombs were planted in mailboxes or trash cans.