An SUV packed with explosives discovered in Times Square -- the shock waves travel to the Southland.
"Just because it happened 3,000 miles from Los Angeles doesn't mean it can't happen here. We've been fortunate," said L.A. County Sheriff's Commander Michael Grossman.
Grossman heads the sheriff's branch of the the Los Angeles Joint Regional Intelligence Center, a nerve center for gathering every tidbit of information that could signal the presence of a terror cell.
"If something were to happen in a transit system somewhere else in the world, we would tend to be more alert here in a transit system. If it's a crowded place, well then you tend to be more vigilant," said Grossman.
Investigators say there is no evidence in the suspected plot by Faisal Shahzad that there is any similar plan for Los Angeles. But experts say it's plain sense to believe sleeper cells could exist here.
Mayer Nudell l is a former U.S. diplomat and an authority on terrorism, and is a professor at Webster University. He says the profile of someone who carries out an attack is evolving.
"More activity by either sympathizers or people who are acting either on their own or in what sometimes is referred to as 'leaderless terrorism,' where they get the idea, but they act on it on their own," said Udall.
Experts are calling it a "terror hybrid." Osama Bin Laden is too penned up to call the shots, but there are others in place who can train a motivated disciple.
And what sorts of things might they do that you might notice? Taking photographs, for one.
"More of infrastructure, the base of a bridge, air conditioning/heating systems in buildings," said Grossman. "In this world of terrorism, in this asymmetric warfare, as we put up one defense, then the terrorists find a way around that defense. So we are constantly playing this cat and mouse game."
Officials are asking the public to be force-multipliers. If you see anything suspicious, report it.