Although both President Barack Obama and the FBI have chosen not to jump into any conclusions about the nature of the explosions, Senator Dianna Feinstein, who is chairwoman of the powerful Senate Intelligence Committee, termed it a terrorist attack, based on her understanding.
Media reports said the federal investigating agencies and law enforcement bodies have increased their check on all outgoing international flights, indicating that they might be looking into the possibility of a foreign link to the attack that sent shock waves to the entire nation. Security of the White House was stepped up soon after the bomb blasts in Boston.
"Out of an abundance of caution, we have expanded our security perimeter at the White House complex. It is not unusual to expand or contract these security perimeters," Secret Service spokesman Edwin Donovan said. Los Angeles Mayor, Antonio R Villaraigosa said the law enforcement agencies have been put on alert.
"We are working closely with our law enforcement partners to monitor the situation and stand ready to aid Boston in any way possible. The LAPD and other public safety agencies will remain vigilant at all public and sporting events in Los Angeles," he said. New York Mayor Michael Bloomberg also said the security in the city has been stepped up following the Boston blasts.
[See: US media deeply worried]