The police chief for the Philadelphia-area's mass-transit system said he has known for some time that more than 140,000 miles of rail lines crisscrossing America are "porous" and had thought for a while of using drones to monitor the agency's tracks.
"It is time that we instill fear and make them impose strict security measures to trains as they did with their air transportation," the publication said.
Amid this threat, Thomas Nestel, police chief for the Southeastern Pennsylvania Transit Authority, told ABC News' David Kerley, that drones are "a great way for us to patrol a track without walking on the track, putting officers in jeopardy safety-wise."
"Using the drone can cover a whole lot of area in a much faster span of time," he said.
"This was bouncing around in my head for a little while and then when that ... article came out, I pulled the trigger, I said, 'Let's do it,'" Nestel said.
The transit-agency's drone, which is equipped with a high-resolution camera, can help officers detect intruders or anomalies on the tracks and provide information that could lead authorities to stop trains before they reach a problem area.
Cohen added, "Securing the rail infrastructure is an incredible challenge. There are literally thousands of miles of tracks. There are rail stations that are open to the public. It's a very difficult job."
Terrorists' targeting of trains is not new. From Madrid to London to Brussels, hundreds have been killed in attacks against commuter trains in Europe.
Threats of rail attacks have hit even closer to home.
And in 2012, an undercover U.S. agent foiled an alleged plot to derail a New York-bound passenger train in Canada.
Still, Cohen said that "for TSA to send out a warning to law enforcement says that, 'We are concerned about this threat; we need you to be concerned about this threat as well,'" Cohen said.
"It's nice that they put out a magazine and let us know what suggestions they provide to their followers," Cohen said of the terror magazine. "Because we're already thinking about how to defeat attacks."
ABC News' Daniel Steinberger and Mike Levine contributed to this report.