Several witness Silver Disc over Baton Rouge

I was fueling my auto in the afternoon at the I-12/Sherwood Blvd. exit in Baton Rouge when I observed a silver disc with portholes at approximately 2-300 ft. altitude over I-12 Interstate. It glided along silently, slightly slower than the traffic. It was observed by me and other patrons, plus the station personell. It was visible for 2 or 3 minutes before disappearing from view. It should have been seen by motorists traveling I-12. We were all amazed and made comments about "the real live UFO".