CBS News' national desk received telephone threats Tuesday against some specific plane flights and scheduled trains.

One of the threats included an Amtrak passenger train that was stopped at the Selma, North Carolina train station at 12:30 EDT. Selma police and emergency crews would only say they were involved in an "incident" involving a train.

Authorities say the train was going from Miami to New York and had previously stopped in Fayetteville.

Bomb-sniffing dogs were used to check out the train and luggage. Passengers were unloaded at the station while officials moved the train about a mile down the tracks. Once officials determined it was safe, passengers reboarded the train and left the station.

Other Amtrak trains mentioned in the threats were stopped and searched, but officials did not find anything.

There were also reportedly threats about bombs aboard two planes in Miami, one in Los Angeles, one in Memphis and one in Detroit. Authorities say all of the planes, except the one in Detroit, were still on the ground when the bomb threats came in.

The plane in Detroit was immediately grounded. No explosives were found on any of the aircraft.