The newest Chicago Police counterterrorism effort will involve assigning officers to high-traffic CTA train stations to randomly check riders’ bags for explosives.

Starting the week of Nov. 3, officers will ask “randomly selected” individuals if they are willing to have their bags screened before they pay to enter a station, police said in a statement Friday. If someone declines the screening, they will not be allowed to ride the train.

The screening process, which police said will take less than a minute, will consist of swabbing bags with a stick capable of detecting explosive material.

If the test comes back clear, riders will be allowed to proceed into the station, police said. If the screening detects possible explosive materials, officers will ask to “inspect the bag and debrief the individual.”

The screening process is similar to one used at Chicago’s Amtrak station and on transit systems in New York and Washington, D.C., police said.

“While there are no credible threats to Chicago or to the region’s public transportation facilities, Chicago is taking this step, as other major cities in the United States and around the world have already done, to ensure the safety of residents and passengers,” Police Supt. Garry McCarthy said in the statement.

“Through this effort we are applying global best practices from major transit agencies, and our own successful efforts from major events.”

Police said the federally funded initiative will involve teams of four or five officers being deployed to high-traffic stations several times a week. The initiative will be implemented one station at a time.