Officials have closed the emergency room at a hospital in suburban St. Louis along with a portion of Interstate 270 after two suspicious packages were found on the hospital campus.

Mercy Hospital officials and Creve Coeur, Missouri, police say the packages were found Monday, one near the helicopter landing area and the other on a sidewalk near the emergency room. The hospital is near I-270, a portion of which was closed as a precaution.

Messages seeking comment from police were not immediately returned.

Hospital spokeswoman Bethany Pope says no patients or workers are in harm's way, but the ER is closed "out of an abundance of caution." Pope says police are investigating the devices to determine if they are explosives.

The rest of the hospital remains open.