On a recent evening, about two dozen residents gathered in recliners and rocking chairs, learning not to trust their eyes in this post-Sept. 11 world.

That mother wandering by with a baby stroller? She might not be so maternal after all. That kindly looking priest? He might have no ties to religion in reality.

Chief Burlington County Sheriff's Officer Leo Vanderbilt had a simple point to get across to his audience: What you see isn't always what you get when you're hunting terrorists.

"Terrorists are not all male, terrorists are not all religious nuts," Vanderbilt told the group. "These people are going to dress just like everybody else in the community."

Residents of this Philadelphia suburb are among a small but growing number of communities across the country that are adding terrorist training to their neighborhood crime watch programs.

Vanderbilt said people should be on the lookout especially if they're visiting a landmark like the Washington Monument or passing a power utility. He said terrorists have been caught overseas disguised as innocent-looking clergymen or moms.

"Law enforcement can't be everywhere," said Tom Faust, executive director of the National Sheriffs' Association, which oversees about 7,500 neighborhood watch groups nationwide.

Expect more neighborhood watch groups to begin learning how to spot suspicious activity. The order to do so came from President Bush, who last year told neighborhood watches to be extra vigilant since the Sept. 11 attacks.

The training in Mount Holly this month was based on the curriculum developed by the New Jersey-based Community Anti-Terrorism Training Institute, organized after the Sept. 11 attacks. Its organizers said it's among the first groups in the nation to devise a plan for teaching residents skills for detecting terrorists.

The idea bothers Deborah Jacobs, executive director of the American Civil Liberties Union of New Jersey, who said the program rings of "Cold War-style fear."

"I'm not sure why we would want to pit neighbor against neighbor and citizen against citizen, or non-citizen," Jacobs said.

Mike Licata, a retired Air Force officer who organized the Mount Holly group, said although smaller communities might not be targets of terrorism, there are good reasons people should be on the lookout.

"A lot of people from Mount Holly jump in their cars and go to center city Philadelphia to go to work," Licata said. "You take that knowledge out of Mount Holly."

Classes so far have been offered around New Jersey and to 450 police officers in Pennsylvania, who are being encouraged to teach it in their communities.

Elsewhere, the Virginia Crime Prevention Association has asked police officers to give neighborhood groups anti-terror materials. And the National Crime Prevention Council, best known for McGruff the Crime Dog, has published a booklet explaining how residents can take a bite out of terrorism.

Patrick Harris, executive director of the Virginia Crime Prevention Association, said teaching neighborhood watches is a good way to implement homeland defense procedures because the groups are already formed and committed.

"All of the sudden after 9/11, some of the things that were important in the neighborhood didn't seem as important," said Lancaster, Pa., police Sgt. Bill Gleason.

The National Sheriffs' Association is trying to double the number of neighborhood watch groups nationwide to 15,000 over the next two years. Many of the groups have shrunk as a result of declining crime rates and aging members.

"It takes something in your neighborhood to go wrong before you realize you need an organization," said Richard Byham, 80, a retired psychologist who helped found the Mount Holly Neighborhood Watch in the early 1980s.

At the training in Mount Holly this month, residents learned about the organizational structure of terrorist cells, likely targets such as national landmarks and embassies, and how people should hide in crowds if they think a terrorist has spotted them.

Vanderbilt pointed out that the hijackers involved in the Sept. 11 attacks went to great lengths to blend in before their deadly mission. The key, he said, is to recognize unusual behavior, such as people who seem to be casing targets.

He suggested neighborhood watchers practice describing what they see and estimating speeds of cars and directions of travel, which might be helpful to police. Being observant is a neighborhood's best defense against any sort of wrongdoing, he said, though he cautioned against overreacting.

"Don't report something just because you haven't seen it or noticed it before," Vanderbilt said.

Many who attended were eager to pitch in with the effort.

"I'm always observant," said 78-year-old Volia Kalabus. "But I'm going to be more so now."