HALIFAX, Nova Scotia -- Regular citizens around the world need to realize they can play a big role in thwarting terrorist attacks, U.S. Homeland Security Secretary Janet Napolitano said Saturday.
"They will be the ones that notice something in the neighborhood, see something on the street," she told a panel at an international forum hosted by the German Marshall Fund public policy group.
"Maybe somebody will pass along a quiet message about 'Hey, these young people have gone over to Somalia. We don't know what they're doing, but now they're back and you may need to know about that,"' she said.
Although there have been no major terrorist incidents in the United States since the Sept. 11, 2001 attacks, police and intelligence services have disrupted 11 plots against New York City alone, officials say.
Last month, a Pakistani-born U.S. citizen who tried to set off a car bomb in New York's Times Square said more attacks on the United States were imminent. He was sentenced to life in prison.
Napolitano said a street vendor had noticed smoke coming from the vehicle and alerted police, who cleared the area. Without that tip, "we may very well have had a serious explosion," she said.
She pointed to the "If You See Something, Say Something" campaign as an example of how the public could be more engaged. The program stresses the importance of reporting suspicious activity to the appropriate authorities.
"The citizens themselves in our countries need to understand ... that they have an important role to play as well," she said.
In the wake of the failed Times Square attack, Napolitano and other security officials said U.S. authorities were having a harder time detecting terrorism threats on American soil.
They said al Qaeda and its affiliates were plotting smaller-scale incidents, such as shootings and car bombings. They also cited a rise of home-grown militants, including about two dozen U.S. citizens who have trained in Somalia.
Napolitano said U.S. local law enforcement authorities also had a big responsibility, since one federal department could not handle all security issues.
"If something happens in the United States, (people) are not going to call the Department of Homeland Security in Washington, D.C.," said Napolitano.
"They're going to call their local police department, so they need to be fully informed and empowered and they need to have information shared with them about techniques, behaviors, tactics that we are receiving."
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