police arrested a man who torched a patrol car with a burning piece of lumber ... and the video shows the officer inside facing a wall of flames.

The Seattle Police Department just released bodycam footage of the wild incident, which unfolded Thursday on the streets of South Lake Union and included a hail of gunfire from cops.

Police say responding officers chased the suspect, who apparently was not struck by the bullets, into a parking garage and used a Taser to take him into custody.

Cops say he was booked into King County Jail and charged with 1st-degree assault and 2nd-degree assault.

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