The FBI is to lead the inquiry into what has been widely described as an “act of terror” but President Barack Obama was more careful in his choice of words.
“We still do not know who did this or why. People should not jump to conclusions before we have all the facts, but make no mistake, we will get to the bottom of this… and we will find out who did this and why they did this. Any responsible individuals, any responsible groups, will feel the full weight of justice,” he said.
As news of the attack spread, the US House of Representatives held one minute’s silence in honour of the victims.
The impact of the security alert was rapidly reflected in other parts of the country. The step-up in police and counter terrorism activity in New York and Washington was routine.