Mexican federal police say they have found a tunnel dug into a border storm drain that leads into the United States.
Federal police say the tunnel was presumably used to smuggle people into the United States.
It appears smugglers dug a lateral tunnel into a main drain. An exit on the U.S. side was hidden by a cover piled over with dirt.
The tunnel may have also been used to move illicit goods, but the police statement did not specify what goods.
Police said Sunday the tunnel was found Thursday in the Mexican border city of Nogales, across the border from Nogales, Arizona. Police found it acting on information they received after discovering another tunnel in Nogales on Aug. 16.