U.S. stock index futures fell Friday with risk sentiment hit by an escalation of Middle East tensions, also weighed by disappointing guidance from tech major Netflix (NASDAQ:NFLX).  

At 06:50 ET (10:50 GMT),Dow Jones Futures fell 140 points or 0.4%, S&P 500 Futures fell 23 points, or 0.5%, while Nasdaq 100 Futures fell 120 points, or 0.7%. 

The main Wall Street indices closed in a mixed fashion Thursday, with the Dow Jones Industrial Average managing to close with small gains. The S&P 500, however, fell 0.2%, logging a five-day losing streak, and the NASDAQ Composite fell 0.5%.

The broad-based S&P 500 is on course for weekly losses of 2.2%, heading for its third straight negative week, and its worst since the end of October last year.

Sentiment weakened after Israel's missile strike on Iran earlier Friday hit risk appetite, escalated tensions in the region and raised the possibility of continuing retaliation between the Middle East powers.