Commodities trading adviser OptionSellers.com suffered losses due to recent volatility in U.S. energy markets, causing accounts to be liquidated, the firm’s clearinghouse, INTL FCStone Inc, said in a statement on Monday.

The liquidation of Tampa, Florida-based OptionSellers accounts comes after one of the most volatile weeks in the U.S. natural gas market in years, as commodities funds scrambled to unwind bets after sudden reversals in the oil and gas futures markets. Read more here