It could be a nervy session for markets Friday as geopolitical tensions shake investor sentiment.
Here are the 5 things you need to know before the opening bell rings in New York:
1. World markets extend slide: World markets fell further on Friday on fear of escalating tensions in Ukraine after a Malaysia Airlines plane crashed in the east of the country.
The U.S. believes Flight MH17 was brought down by a surface-to-air missile over a region that has seen heavy fighting between pro-Russian separatists and Ukrainian government forces.
Analysts say the tragedy could damage business confidence, particularly in Europe, but may also bring the crisis in Ukraine to a head by increasing the pressure on Moscow to resolve the conflict.
2. U.S. futures flat: U.S. stock futures were holding steady after Thursday's sharp sell-off, which gathered pace on news that Israel had sent ground troops into Gaza.
The flurry of geopolitical concerns sent the VIX (, a key measure of )market volatility to its highest level in three months Thursday.
The Dow Jones Industrial Average lost 161 points, while the S&P 500 was off about 1.2%, and the Nasdaq finished down 1.4%. It was the biggest drop for the Dow in two months, and the S&P's fall is the biggest for the index in three months.
3. Earnings season continues: General Electric ( and )Honeywell ( will report earnings before the opening bell. )
Google (Tech30) shares gained 1.7% premarket after the company reported another quarter of , surging sales growth. News that Japan's Softbank has hired away Google's global sales chief Nikesh Arora may pique investor interest.
4. Economic data diary: The University of Michigan will post its consumer sentiment measurement at 9:55 a.m. ET.
5. Tax inversion deal: Drugmaker AbbVie ( could unveil a deal to buy )Shire ( as early as Friday, according to reports. )The $54 billion acquisition would be the latest by a U.S. firm looking to move its tax base overseas to save money.