Due to the extent of his injuries, D.C. Metropolitan police have yet to identify the man. DNA and dental records will be examined, police spokesman Officer Araz Alali told CNN.
The incident took place Friday near the Air and Space Museum, about six blocks from the Capitol. Witnesses reported seeing the man sitting, engulfed in flames with a red gasoline canister nearby.
It remains unclear what caused the man to self-immolate.
The incident is the second bizarre death near the Capitol in as many days. A Connecticut woman's car chase ended their when police shot her to death Thursday.
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