The Miramar, Florida-based discount airline is expected to file for bankruptcy protection from its debts in as little as 10 days or within weeks, sources familiar with the matter confirmed to CBS News. The Wall Street Journal first reported the looming bankruptcy filing.

KEY TAKEWAYS Spirit Airlines shares are plunging more than 60% in premarket trading on a report that the budget carrier is getting ready to file for bankruptcy protection after revived merger talks with Frontier Airlines parent Frontier Group Holdings collapsed.

Spirit Airlines' stock plunged 59% on Wednesday as the budget airline worked with creditors to restructure debt amid reports the company could file for bankruptcy protection within the next few weeks.