SYRACUSE, N.Y. (AP) _ Fallen tree limbs are being blamed for a power blackout that left several thousand customers in Syracuse in the dark for more than three hours Thursday night. Large portions of the city's south side and most of the Syracuse University campus went dark around 6 p.m. National Grid crews patrolling the lines found the downed tree limbs on primary wires near the campus. Company spokesman Stephen Brady says the limbs caused a fault, which in turn caused breakers at a nearby substation to open, killing power. At the height of the blackout, National Grid reported more than 6,000 customers without power in Syracuse and about another 500 each in the towns of DeWitt and Onondaga. No injuries were reported despite the frigid cold.