Futures rise after China injects 140 billion yuan

US stock index futures were sharply higher on Wednesday after China's central bank said it injected 140 billion yuan ($21.8 billion) into the interbank money market.

U.S. stock index futures were sharply higher on Wednesday after China's central bank said it injected 140 billion yuan ($21.8 billion) into the interbank money market.

S&P 500 e-minis were up 23.5 points, or 1.25 percent, with 407,357 contracts traded by 6:05 a.m. ET (1005 GMT).

Nasdaq 100 e-minis were up 46.5 points, or 1.15 percent, on volume of 64,390 contracts. Dow e-minis were up 179 points, or 1.14 percent, with 41,507 contracts traded.

(Reporting by Tanya Agrawal; Editing by Ted Kerr)