Burn

From Wikipedia:

A burn bag is the informal name given to a container (usually a paper bag or some other waste receptacle that holds sensitive or classified documents which are to be destroyed by fire or pulping after a certain period of time. The most common usage of burn bags is by government institutions, in the destruction of classified materials.

Destruction via burn bags is considered superior to shredding, because shredded documents may be reconstructed. After the capture of the United States embassy in Tehran during the Iran hostage crisis, shredded documents were turned over for painstaking manual reconstruction, which revealed to Iran some U.S. operations including spies.

Today, scanners and computers can reconstruct shredded documents very quickly. Burn bags are designed to facilitate the destruction process by not requiring the removal of the items to be destroyed beforehand and by indicating if the items require special procedures.