The incident happened on Tuesday.
Video released by the district attorney's office shows a man spraying the flag with red dye or paint.
Action News was there earlier this week when another suspect, 26-year-old Antoine Guyton, was arrested.
He was originally charged with vandalism, but charges were rescinded when video emerged showing a different man defacing the flag.
However, investigators say Guyton did play a role in the vandalism and are planning to re-arrest him on different charges.
Anyone with information is asked to contact Philadelphia police.
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