Options trading in large stock and currency ETFs shows some investors are moving toward a risk-off stance as the S&P 500 drops back below the key 1,400 level.

Buyers of protection via downside puts in SPDR S&P 500 (NYSEArca: SPY) emerged on Wednesday as equities finished near their lows for the day, said Paul Weisbruch, head of ETF/options sales and trading at Street One Financial.

Stock opened lower Thursday, with the Dow shedding over 100 points.

“Good sized call buyers were present in PowerShares U.S. Dollar Index Bullish (NYSEArca: UUP) yesterday, and we have pointed out similar activity [recently]with put buying in CurrencyShares Euro (NYSEArca: FXE),” Weisbruch wrote in a note to clients Thursday.