A major rescue operation is now under way.
A statement from the Colombian air force said that a helicopter was on the way to the Penol reservoir near the town of Guatape, which is approximately 45km east of Colombia’s second largest city of Medellin.
The mayor of Medellin has said that firefighters and scuba divers from the city are now travelling to the Penol reservoir.
It is not yet clear whether there have been any casualties or where the tourists were from, but videos on social media suggest that a recreational ferry has sunk in the reservoir.
