(Reuters) - U.S. stock index futures extended declines on Friday after nonfarm payrolls rose less than expected in July, spurring worries about the health of the U.S. economy.

The Labor Department's report showed nonfarm payrolls rose by 114,000 jobs in July, where economists polled by Reuters forecast an increase of 175,000.

The unemployment rate ticked higher, to 4.3%, from 4.1% a month ago.

At 12:33 a.m. ET, Dow e-minis were down 486 points, or 1.2%, S&P 500 e-minis were down 91.75 points, or 1.67%, and Nasdaq 100 e-minis were down 447 points, or 2.35%.