Spirit Airlines disclosed it is in talks with its creditors for a restructuring deal, hours after it was reported that the company’s merger talks with rival low-cost carrier Frontier had fallen through.

Spirit Airlines Inc.’s stock cratered 55% Wednesday, on track for its biggest-ever one-day decline, after the company warned that its equity would be wiped out as part of a restructuring deal that it’s currently negotiating with its creditors.

Spirit Airlines stock tumbled in premarket trading Wednesday following a report that said the ultra-low-cost carrier was preparing to file for bankruptcy protection.The filing could come within weeks,