What factors increased the destruction during and after the 1906 san francisco earthquake?

Uncontrolled fires due to the destroyed city’s water mains and property owners that set fire to their damaged properties to receive indemnification.

Explanation:

The earthquake occurred on April 18, 1906, at 5:13 a.m., with its epicenter offshore of San Francisco (population of 400,000 people), its magnitude was 7.9.

The quake ruptured a total of 290 miles of the Earth's surface extending from San Juan Bautista in San Benito county to Humboldt county. The shaking was felt from Los Angeles in the south to Coos Bay, Oregon, in the north.

The greatest devastation resulted from the fires that quickly followed the quake, the initial tremors destroyed the city’s water mains, leaving firefighters with no means of combating the growing blaze, more than 3,000 people perished and more than 28,000 buildings were destroyed in the disaster approximately 90% of the total destruction was the result of the subsequent fires, some property owners even set fire deliberately to their damaged properties in order to receive an indemnification.

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