Story highlights Boat sank in reservoir near Medellin

Officials say roughly 170 were on board

(CNN) The Colombian Air Force, Army, firefighters and divers combed the waters of a man-made lake in the resort town of Guatape on Monday, looking for survivors after a tourist boat sank the day before.

Colombian emergency officials announced the death toll had risen to seven, but added that only two people remain missing. Dozens were unaccounted for after the boat first went down.

158 people have been rescued, authorities said. Previous estimates put the total number of people on board the boat at about 170.

Tourist boat El Almirante is seen taking on water in the Guatape, Antioquia on June 25, 2017.

The incident happened about 45 kilometers (28 miles) east of Medellin, one of Colombia's biggest cities.

The search for the missing continued Monday after thunderstorms forced rescue teams off the water last night. Colombia's President Juan Manuel Santos said the search would resume at first light.

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