Chicago commuters may start seeing federal security personnel joining them on train rides to and from work.

Metra says teams from the federal Transportation Security Administration will begin patrolling its trains soon.

A Metra statement says they'll work with existing security to bolster detection and deterrence. It adds the intention is to use unpredictability to disrupt potential terrorist planning activities.

The statement says the initiative isn't a response to any specific threat.

The teams may also include federal marshals and TSA-certified dogs. Members will wear identifiable uniforms while on patrol.

Federal authorities stepped up train security nationwide following deadly train bombings in Madrid in 2004.