President Obama has described the bombing of the Boston marathon as an act of terrorism.
In a short briefing from the White House the president praised the efforts of the emergency services, the people of Boston and the exhausted runners who still had the energy and presence of mind to assist the injured: “This was a heinous and cowardly act. Given what we know now what took place. The FBI is investigating an act of terrorism. What we don’t know yet is who carried out the attack, or why, whether it was planned and executed by a terrorist organisation, foreign or domestic, or the act of a malevolent individual. It will take time to follow every lead and determine what happened , but we will find out,” he said.
The FBI and Boston police are combing through tens of thousands of digital photographs, CCTV footage and TV broadcasts on one of the most documented events in the city’s calender.
Authorities say there will be an increased security presence in Boston over the coming days.
Superintendent Timothy Allen from Boston police: “You’re going to see an enhanced presence from the Boston Police, from the State Police, from the National Guard and from our law enforcement partners from Metropolitan Boston. You might also see an enhanced presence in the airports as well. This is not for any particular reason again, other than to seek cooperation from the public in order to gain information.”
As the officer spoke an aircraft underwent security checks on the tarmac at Logan Airport amid concerns over an unclaimed piece of luggage.
The United States is on alert.