
Two people have been killed and around 100 injured after two explosions ripped through the finish line of the Boston Marathon.
The near-simultaneous blasts occurred at 2:50pm local time, as runners finished the marathon, around three hours after the winners had crossed the line.
TV footage showed streets littered with blood and injured people after runners were cut down by flying debris. Dozens of casualties were taken from the scene on stretchers and in wheelchairs.
Police are hunting for more explosive devices and the Massachusetts governor Deval Patrick says more than 100 people have been injured.
US president Barack Obama has vowed to bring those responsible for the blasts to justice and the White House says it is treating the explosions as a terrorist attack.