Asian stocks were mixed on Wednesday amid concerns about global growth and renewed unrest in the Middle East.
Data on Tuesday showed business activity in the euro zone falling to a nine-month low in September, with growth in both manufacturing and the services sector slowing, which weighed on global markets overnight. The S&P 500 and Nasdaq fell for a third session to close at five-week lows, while European indices lost over 1 percent each.
Evan Lucas, market strategist at IG, points to the recent decline in copper prices as a harbinger of future trading action. The metal hovered near three-month lows following China's mixed factory data on Tuesday.
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"As the clearest measure of future industrial production, the copper slide is a telling reminder that short-term volatility and downward pressure is likely over the coming months. Investors are starting to believe the People's Bank of China and central government want structural change to take effect," he said in a note.
Sentiment was also cautious after the U.S. began its first airstrikes against Islamic State (IS) fighters and targeted IS assets in eastern Syria alongside Arab allies. President Obama also mentioned strikes against the Khorasan Group in Syria, an off-shoot of Al Qaida.