US stocks
A specialist trader watches developments following the explosions in Brussels, on the floor of the New York Stock Exchange (NYSE)Reuters

US stocks closed with a mixed picture on 22 March following news of the terrorist attacks in Brussels that left at least 34 people dead. The Dow Jones snapped its seven-day win streak, as the S&P 500 broke its own four-day win streak. The Nasdaq Composite, meanwhile, outperformed and posted its first five-day win streak since April 2015.

The Dow Jones Industrial Average dropped 41.30 points, or 0.2%, to settle at 17,582.57. According to MarketWatch, Goldman Sachs Group contributed to declines, cutting around 14 points from the Dow. UnitedHealth, which rose 1.32 points or 1.04%, continued to most to gains on the blue-chip index.

According to CNBC, Dow transports underperformed, dropping almost 0.8% with lead decliners Union Pacific (-2.29%) and American Airlines (-1.63%). Norfolk Southern (+0.31%) and Avis Budget (+0.03%) were the only ones to contribute to gains.

"The tragedy just reminds us we're living in a dangerous world," said Art Hogan, chief market strategist at Wunderlich Securities. "We've got a market that's focused on the human side versus the economic side, which is the right thing to do," he added.

The S&P 500 gave up modest gains to end down 1.80 points, or 0.1%, settling at 2,049.80. Consumer staples, led by Modelez International, were the biggest decliners to the index. CNBC reported that healthcare ended up 0.9% to lead gains.

Unlike the Dow and S&P 500, the Nasdaq outperformed, posting gains of 12.79 points, or nearly 0.3%, at 4,821.66. Apple, which closed 0.76% higher, and the iShares Nasdaq Biotechnology ETC (IBB), which ended up 2.58%, contributed to gains.

"It's been a pretty impressive response by stocks we had today given the news we had overseas and the run we've had over the last couple weeks," explained Jeremy Klein, chief market strategist at FBN Securities.

US crude oil futures dropped 7 cents to settle at $41.45 (£29.14) a barrel.

Meanwhile, treasury yields traded higher, with the 2-year yield at 0.89% and the 10-year yield at 1.94%. The US dollar index held 0.3% higher, with the euro near $1.1223, the yen at 112.30 yen against the greenback and the sterling hit 1.4212. Gold futures ended up 0.4%, or $4.40 to settle at $1,248.60 an ounce.

Abroad, European stocks closed mixed, with the German DAX ending 0.4% higher and the STOXX Europe 600 down 0.15%. "I think we're just following Europe, which closed well off their lows. ...If they're shrugging it off, we're shrugging it off," said Peter Boockvar, chief market analyst at The Lindsey Group. "If Europe closed up, why shouldn't we? That's the mentality," he added.

Asian stocks also closed mixed, with Japan's Nikkei 225 up almost 2% and the Shanghai Composite around 0.6% lower.