A foiled terror plot in New York is raising questions about whether the Department of Homeland Security is focused on the threat of "radicalized" Muslims in the U.S. after the department issued a controversial report last month warning instead of right-wing extremists.
The report forced Homeland Security Secretary Janet Napolitano to apologize to veterans for language that said disgruntled troops returning from the wars in Iraq and Afghanistan were at risk for being recruited by extremists.
A Homeland official told FOXNews.com on Thursday that the report focused on white supremacy groups, not radicalized Muslims, but the agency is monitoring all terror threats.
"It's fair to say that homegrown terrorism is a serious threat and something that law enforcement agencies and the government are taking seriously at the federal and local levels," he said. "This is something that people have been concerned about for a number of years."
An informant helped the FBI arrest four homegrown terror suspects Wednesday night following a nearly yearlong undercover investigation that revealed a plot to blow up two synagogues in New York City and to shoot down planes at an Air National Guard base.
"Neither DHS nor the FBI has any credible information indicating any further threat to the homeland," Sean Smith, a Homeland Security spokesman, told FOXNews.com. "But we do continue to urge vigilance and ask all Americans to report any suspicious activities or information to appropriate authorities."
Sen. Joe Lieberman, I-Conn., chairman of the Homeland Security Committee said his panel will continue its three-year, bipartisan investigation of the issue to the monitor the threats and assess government efforts to prevent and combat it.
"This alleged plot shows that -- even though we have not been attacked domestically since 9/11 -- we must remain vigilant concerning the potential radicalization and recruitment of individuals in the United States for terrorist activity."
The alleged plot to blow up two synagogues and shoot down a military plane in a holy war against Jews and the United States began with a conversation in a modest mosque in Newburgh, N.Y., federal prosecutors say.
Rep. Peter King, R-N.Y., the top Republican on the House Homeland Security Committee, told a New York radio station that the incident was another example of the FBI doing its job.
"I hope we don't see recriminations now from people saying they shouldn't have been looking at a mosque or it was wrong to look at a mosque," he said. "The fact is there are a number of mosques. They're under surveillance, they're being watched, not because they're mosques per se but because mosques is where this comes from."