The stock fell 76 cents to $5.48.
Investors also took cover in the yen, the Swiss franc and gold.
The tech-heavy Nasdaq composite bore the brunt of the sell-off, losing 135.46 points, or 2.1 percent, to 6,216.87.
After seeming to shrug off the heated rhetoric between U.S. President Donald Trump and North Korea over the last couple of days, investors are becoming more wary as the standoff between the two countries continues ratcheting up, said Michael Currie, vice-president of TD Wealth Private Investment Advice.
Earlier, Trump warned North Korea on Tuesday it would face "fire and fury" if it threatens the United States, prompting the nuclear-armed nation to say it was considering firing missiles at Guam, a USA -held Pacific island.
Trump followed his warning with a tweet yesterday about the strength of the American nuclear arsenal, but expressed hope it would not need to be used.
Gold prices posted strong weekly gains (http://www.marketwatch.com/story/gold-heads-for-strong-weekly-gain-as-stock-market-exit-persists-2017-08-11) thanks to safe-haven demand. But the moves were modest.
Gold prices picked up $7.40 to $1,286.70 U.S.an ounce.
The common currency had lost about 0.4 percent overnight after news USA job openings surged to a record in June reinforced Friday's robust payrolls data and supported the greenback.
The loonie was shaking off its slumber in late morning trading today after racking up losses for more than a week.
"Of course it's all come at a time when share markets are due for a correction, so North Korea has provided a flawless trigger", he added.
RETAIL SLUMP: Disappointing quarterly results from big department store chains put investors in a selling mood.
Priceline sank 6.9 per cent as it projected third-quarter earnings below analyst expectations. Netflix lost 1.5 per cent.
Shares in several other big media companies also declined.
In Paris, Engie fell 1.12 percent on reports that it is in talks to purchase a wind power project in Brazil. The company booked a hefty charge and said its CFO is leaving the company. The stock lost $2.36 to $20.67. The stock has more than doubled over the past 12 months, gaining more than 160%.
The geopolitical turmoil appeared to have more of an impact overnight and into early Wednesday. It slid 80 cents, or 1.5 percent, to close at $51.90 per barrel on Thursday.
The pan-European Stoxx Europe 600 index weakened by 0.73 percent.
Overseas, European markets were trading lower by noon on the continent, while the Nikkei 225 in Japan doffed 0.1%, and Shanghai's CSI 300 fell 0.4%. Two weeks ago it saw its biggest weakly fall against the euro since the start of 2015.
The dollar weakened after news that USA producer prices unexpectedly fell in July, recording their biggest drop in almost a year and pointing to a further moderation in inflation that could delay a Federal Reserve interest rate increase.
Oil prices gained 60 cents to $50.16 US per barrel.
Charter Communications rose 2.9 per cent on news Altice is exploring a bid for the cable giant.
The 30-year bond was last up 4/32 in price to yield 2.7871 percent, from 2.794 percent late on Thursday. Copper fell 2 cents to $2.90 a pound.
The dollar strengthened against the Swiss franc on Thursday, buying 0.9642 franc compared to 0.9636 franc late Wednesday in NY. The euro held steady at $1.1752.