Markets plunge over global economic concerns

Concerns about the global economy sent the markets tumbling to a sharply lower open with the Dow plummeting 248 points to 16,426. Nasdaq plunged 48 points to 4,845.

On the upside

AK Steel (NYSE: AKS) forecast a smaller than expected loss for the third quarter.

Kinross Gold (NYSE: KGC) lowered its 2015 all-in sustaining cost, cost of sales and capital expenditure guidance.

Tracon Pharmaceuticals (Nasdaq: TCON) reported positive results from an ongoing compassionate use Phase 2 clinical trial of TRC105.

On the downside

La Quinta Holdings (NYSE: LQ) chief executive Wayne Goldberg resigned and the company lowered its full year outlook.

Freeport-McMoRan (NYSE: FCX) completed its $1 billion common stock offering and filed to sell up to $1 billion in additional shares.

Parsley Energy (NYSE: PE) priced its public offering of 13 million common shares at the discounted price of $15 per share.

In the broad market, declining issues outpaced advancers by a margin of nearly 9 to 1 on the NYSE and by more than 6 to 1 on Nasdaq. The broader S&P 500 plunged 24 points to 1,966. Bitcoin eased a fraction to $231.