SIOUX CITY, Iowa (AP) – The Argosy riverboat casino on Sioux City has sent layoff notices to all of its more than 300 workers. The notices were sent Wednesday in accordance with a federal law that requires employers with more than 100 employees to provide at least 60 days’ notice of a workplace closing or mass layoff. But Argosy’s parent company, Penn National Gaming Co., says it is not ending its fight to keep open the casino.

The Argosy’s pending closure stems from the Iowa Racing and Gaming Commission’s decision to allow a land-based casino in downtown Sioux City to replace the Argosy. Penn National lost its bid to operate the land-based casino to Sioux City Entertainment, which is building and will operate a Hard Rock Casino.