A massive wall of water from three overflowing rivers in southwestern Colombia swept through the town of Mocoa overnight Friday as residents slept, destroying homes and infrastructure and killing nearly 200 people.

President Juan Manuel Santos visited the wrecked town of 40,000 near the border with Ecuador on Saturday and declared a state of public calamity.

Santos warned the death toll is likely to rise, and added, “We don’t know how many victims there are going to be.”

To those affected by the disaster, he said, “We will do everything possible to help them. It breaks my heart.”

For their part, Red Cross officials said 400 people were injured in the deluge, with at least 220 others missing.

Video from the scene showed flattened buildings and mounds of crumpled cars and uprooted trees, as dazed residents surveyed the scene and rescuers pulled the injured and the dead from the wreckage.

The catastrophe came after days of torrential rains that left large parts of the region without electrical power or running water.

In recent months, heavy rains and flooding have struck along the Pacific side of South America, killing scores of people in Peru and Ecuador.

WATCH: Video of flooding
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