(AP) - Mattress Firm, Inc., the nation's largest mattress retailer, is filing for bankruptcy protection and plans to close up to 700 stores around the country.

The Houston-based company filed for Chapter 11 bankruptcy protection Friday in federal court in Delaware.

According to court documents, Mattress Firm has more than $1 billion in liabilities and has more than 50,000 creditors. It owes its largest creditor, mattress maker Simmons Manufacturing Co., nearly $65 million.

In a statement, CEO and president Steve Stagner says the bankruptcy filing will allow the company to "strengthen our balance sheet" and close stores in certain markets with "too many locations in close proximity to each other."

The company has more than 3,000 stores in the U.S. and in recent years had been aggressively expanding as it purchased competitors.