The ice block dropped into a lake in the Andes on Sunday, Apr 11 near the town of Carhuaz, some 200 miles (320 km) north of the capital, Lima. Three people were reportedly buried in the debris.
According to investigators, the ice block which fell from Hualcan glacier measured 1,640 feet by 656 feet.
"This slide into the lake generated a tsunami wave, which breached the lake's levees, which are 23 m high -- meaning the wave was 23 m high," said Patricio Vaderrama, an expert on glaciers at Peru's Institute of Mine Engineers.
Fearing more breakages, the authorities have evacuated the mountain valleys.
The incident has revived concern about the melting of glacier in Peru, which is home to 70% of the world's tropical icefields.
Scientists predict that warmer temperature would lead to the complete disappearance of the glaciers within 20 years.
In 1970, more than 20,000 people in the town of Yungay were killed after an earthquake triggered an avalanche of ice, rock and mud on the mountain of Huascaran that buried the entire town below the peak.