Boston attack 'easily' one-man operation, say bomb experts

The bombing at the Boston Marathon that claimed at least three lives and injured over 140 others is likely a one-man operation and it was virtually impossible to prevent such attacks in a free country, US security experts warned today.

They said the bombs could easily have been hidden in a backpack, avoiding all suspicion among the thousands of spectators who flooded the Back Bay yesterday.

Retired FBI bomb technician Kevin G Miles said the attack could "easily" have been the work of one person.

"A one-man operation could easily do something like this," Miles was quoted as saying by the Boston Herald.

"It would take some coordination, some know-how and some intelligence, but a lot of bombers throughout history have been one person."

Miles also said it would have been all too easy for the bomber or bombers to blend in.

"There are thousands and thousands of people. You're not going to be able to check everybody's backpack, everybody's gym bag. Every runner's got a backpack... We're a free country. This isn't Russia or Cuba."

The white smoke was indicative of a "commercially available explosive," such as smokeless gunpowder, Miles said.

He, however, said there is nothing to immediately indicate whether it was the work of a team or a lone wolf.

While Grant Haber, a security consultant who runs the firm American Innovations, said that when the "terrorist has planned an attack and they're going to utilise an IED as their weapons of strategic influence, it's hard to stop that in a free and open society".

Authorities confirmed nothing about suspects and provided no details about the types of devices used.