A continued fall in the price of oil and a rout in Chinese stocks weighed on investor sentiment on Tuesday, with global equities seeing heavy losses during the session.
The German DAX, French CAC 40 and U.K.'s FTSE 100 all slipped over 1 percent at the open, with the pan-European Euro Stoxx 600 index down 1.24 percent in early trading. Meanwhile, Greek stocks slid 6 percent, with continued political jitters in the country adding to the declines.
U.S. stock futures were also pointing lower, indicating triple-digit losses for the Dow Jones at around 8:00 a.m. GMT, before trimming losses as the European session gathered pace.
China was the main focus for investors as the country's Shanghai Composite benchmark tumbled in the final hour of trade. It finished the session down 5.3 percent after rallying to a three-and-half-year high of 3,091 points earlier in the day. It marked its biggest one-day fall in percentage terms since August 2009.
"It's not a stock market, it's a casino," Peter Elston, a global investment strategist at Seneca Investment Managers, told CNBC about the Chinese benchmark.