Law enforcement agencies in Nassau and Suffolk counties are stepping up patrols in the wake of deadly attacks in Paris and San Bernardino, California.

Officials say the two suspects in the San Bernardino attack were not on any federal terror watch lists.

Authorities say the couple had accumulated a large stockpile of deadly weapons, but had never showed up on the radar of various law enforcement agencies. 

Timothy Sini, the Suffolk County deputy police commissioner, says local police must step up patrols in crowded places while preparing to defend so-called soft targets, which are increasingly targeted in terror attacks.

In addition to conducting active-shooter training drills, Sini says police have been sharing defense strategies with potential targets.

In Nassau, police have also acquired an additional 150 semiautomatic weapons for rapid response teams to help thwart an attack.

Terrorism expert Harvey Kishner says that in the aftermath of the attacks in Paris and San Bernardino, the threat of copycats and lone-wolf attacks should prompt the public to become more vigilant.

"Twenty-four-seven, we're under attack," Kishner says. "You can't let your guard down, but you know what? We have to go about our daily business."

Sini also says that Nassau and Suffolk may jointly engage in training drills in the near future.