(CNBC) U.S. stocks closed mildly lower on Thursday as equities failed to shake off the losses of the last three days and investors weighed geopolitical events ahead of earnings season.
"I'm a little disappointed the market couldn't continue (higher) after last week," said Bruce Bittles, chief investment strategist at RW Baird. "It suggest something's not quite right."
He noted overwhelmingly bullish sentiment amid the recent selloff, which "suggests to me a tired market. It's a little complacency plus you've got first quarter earnings ahead.