WH: 'Closely following' kidnapping of Americans in Mexico

STORY: "Our thoughts are with the families of these individuals and we stand ready to provide all appropriate consular assistance and U.S. law enforcement is in touch with Mexican law enforcement," Jean-Pierre told reporters.

The four unidentified Americans were in a white minivan with North Carolina license plates when they entered Matamoros, Tamaulipas, on Friday, the U.S. embassy to Mexico said in a statement, seeking the public's help in identifying the alleged kidnappers.

The armed men allegedly fired on the passengers shortly after their vehicle crossed into Mexico and then herded them into another vehicle before fleeing the scene, the embassy said.