U.S. manufacturing growth accelerated in May for the first time in six months, propelled by more new orders and an increase in hiring.

The Institute for Supply Management, a trade group of purchasing managers, says that its manufacturing index rose to 52.8 last month, from 51.5 in April. That's the highest reading since February. Any reading above 50 signals expansion.

A measure of production fell, but it remained above 50. A gauge of new orders rose to the highest level since December, a sign production should pick up in the months ahead.

And a measure of employment jumped to 51.7, after falling below 50 in April. That means manufacturers added jobs last month.