A rocky avalanche that then triggered a massive mudslide struck the town of Bondo, Switzerland, near the Italian border on Wednesday.

The disaster unfolded quickly and with force. An estimated 140 million cubic feet of debris came crashing down the mountain. A senior Swiss police official told the Associated Press that the impact registered 3.0 on the Richter scale. Buildings were ripped apart by the fall, and nearly 100 people had to be evacuated. (See how a landslide triggered a deadly tsunami in Greenland.)