U.S. industrial output edged up just 0.1 percent in May as supply chain disruptions from the earthquake in Japan disrupted auto production for a second straight month, the Federal Reserve said on Wednesday.

Despite a 1.5 percent drop in auto production, manufacturing output rose 0.4 percent as factories made up for production lost in April because of tornadoes in the South.

Overall industrial production was also supported by a 0.5 percent gain in mining production, the Fed said.

Economists had looked for a 0.2 percent increase in industrial output.

Capacity use, a measure of how close firms are to running their facilities at maximum capability, was flat at 76.7 percent, below the average over the past three decades.

Analysts had expected a slightly higher capacity use rate of 77 percent.

(Reporting by Rachelle Younglai, Editing by Chizu Nomiyama)