San Antonio fire department arson investigators are looking into the cause of suspicious fires that destroyed two school buses and a truck and damaged a portable at a school. Firefighters responded to the scene early Sunday morning at the Higgs, Carter, King Charter Gifted and Talented Charter Academy. The San Antonio Express-News reports that 1 of the burning buses and the burning truck were near the portable building. The second bus was found engulfed in flames away from the first fire.