After a torrid day on Wall Street Thursday, the worst to hit the markets in 18 months, U.S. stock index futures were pointing to another lower open on Friday.
The Dow futures were off 80 points, indicating a milder extension of Thursday's plunge.Â
Stocks sold off Thursday with the Dow down 358 points to 16,990 and the S&P 500 off 43, or 2.1 percent to 2,035. The selling was fueled by global growth concerns and uncertainty about when the Fed will move to raise interest rates.Â
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In Asia, Friday morning saw the  Shanghai Composite slide 4.3 percent after disappointing data from China.Â
European markets also plunged, with the pan-European Stoxx 600 as much as 1.2 percent lower after the open amid worries over China and also Greece, where Prime Minister Alexis Tsipras resigned and called snap elections, expected to take place in September.Â
The only U.S. data out Friday is the manufacturing PMI report at 9:45 a.m. ET.
The dollar traded mixed, stronger against emerging market currencies and weaker against the euro, which crept towards $1.13.Â
In oil markets, Brent crude was trading at $46.38, down 0.51 percent, while U.S. crude was $41.12 a barrel, down 0.48 percent. This week saw U.S. crude hit a new six-and-a-half-year-low.Â
On the earnings front, Deere and Foot Locker reported results before markets open.Â
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Deere earned $1.53 per share for its third quarter, 9 cents above estimates. However, revenue was below forecasts and Deere also lowered its forward guidance. The company said it is being impacted by a downturn in the farm economy and lower demand for construction equipment.
Foot Locker earned 84 cents per share for its second quarter, 15 cents above estimates. Revenue was above analysts' forecasts as well, and a same-store sales increase of 9.6 percent exceeded estimates of a 6 percent rise.
CNBC's Peter Schacknow and Patti Domm contributed to this reportÂ