Transcript for Syrian Electronic Army a Credible Threat
Here at home, the fbi and department of homeland security are focusing on the possibility of retaliation. They sent out a classified intelligence bulletin to law enforcement agencies all over this country. Our chief justice correspondent, pierre thomas, is covering that angle from washington. Pierre, what are the specific concerns here? Reporter: Good morning, dan. No specific threat has been identified. But the people we pay to protect the united states are already focusing on potential threats. Here's what they're concerned about. Syrian nationals who come to the u.S. Who may be operatives of the assad government or sympathizers. And there's real concern about cyber attacks. The syrian electronic army, a group of hackers that supports the assad regime, is a real threat, sources say. As one official told me, they are, quote, more than a nuisance. They're thought to be behind an attack that knocked out "the new york times" website earlier this week. Pierre, if this missile strike is launched against the syrians, and it could come today, if we hear, if that happens, will we see stepped up signs of security here at home? Reporter: Absolutely. You will see stepped up security at airports and other transportation hubs. There will be seen and unseen additional security throughout the u.S. No specific threat. But no one's going to take any chances, dan. Nobody taking any chances. Pierre thomas, our chief justice correspondent. Pierre, thank you. Abc's "this week" follows the latest on the crisis in syria tomorrow morning with george stephanopoulos.
This transcript has been automatically generated and may not be 100% accurate.