PHILADELPHIA (CBS) —  Philadelphia Police Commissioner Charles Ramsey is speaking out on the Paris terror attacks and keeping the city safe.

In a one-on-one interview, Ramsey told CBS 3’s Walt Hunter that not long after the attacks began, he was on the phone with the Special Agent in Charge of the FBI Office in Philadelphia,”to talk about what’s going on. More importantly, how does this impact the United States, Philly in particular?”

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Ramsey told Hunter the terrorists’ choice of so-called “soft targets” like restaurants and a concert hall makes it even more crucial for everyone to be on the alert.

“If you see something suspicious, it probably is suspicious. Give us a call,” Ramsey said.

Finally, the Commissioner warned, tracking terrorists is now becoming harder than ever because they are perfecting high-tech ways to keep their communications secret.

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“So when you hear us talking about chatter, monitoring this and monitoring that, there will come a time when there will be no chatter to listen to,” Ramsey explained.

It’s called “going dark” — using encrypted communications that are impossible to intercept.

“You aren’t able to penetrate this stuff,” the Commissioner cautioned, “so they’re going to be ‘below the radar,’ with no warning and
they’ll be able to carry out these very, very barbaric acts.”

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Ramsey urged the public to contact legislators, asking them to pass laws that will make it possible to continue monitoring terrorists’ activities.