CHICAGO — Metals fabricators and primary metals producers saw capacity utilization rates increase last month, along with the indices for industrial production, the Federal Reserve Board said Wednesday.

Fabricators reported particularly good news, with capacity utilization rising to a six-month high of 83.5 percent. Capacity utilization for metals producers stood at 76.6 percent, up just 0.2 points from April but still 1.8 points lower than February.

The industrial production index for fabricators rose 0.8 percent in April to the highest level in at least six months, while the index for producers inched up 0.1 percent.

Mining production increased 1.6 percent in April after dropping 1.7 percent in March. Capacity utilization in mining moved up to 88.8 percent in April and was 1.5 points above its long-run average.

For the United States as a whole, industrial production increased 1.1 percent in April, with manufacturing output up 0.6 percent after a 0.5-percent fall a month earlier.