How does Katniss know District 4 is rebelling?

District 12 is the poorest of the 13th districts in the Panem. Its main economic activity was the extraction of minerals from the coal mines which were located there.

During the rebellion, The Capitol decide to bomb District 12, leaving mass destruction throughout the territory. The site was used as a transportation base to take rebel troops to The Capitol. After the war and upon her return, Katniss decided to build a medicine factory that would help aid the residents who affected by the war.

Explanation:

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