McGraham was doused with flammable liquid and set on fire as he slept on the corner of Third and New Hampshire earlier this month.
Witnesses describe the suspects as Latino men in their mid 20s.
The L.A. City Council is offering a $75,000 reward for information leading to an arrest. Anyone with information is urged to call (877) LAW-FULL, or (877) 529-3855.
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