An effort by the federal government to sell the two former Hawaii Superferry high-speed catamarans has attracted four interested buyers, though it is not certain when or whether a winning bidder will be picked.

The U.S. Department of Transportation’s Maritime Administration said Monday it received four bids to buy the two ships, the 321-foot Alakai and 338-foot Huakai. But the agency said it cannot identify the bidders nor say when it might complete its review of the bids.

“We are at the very beginning of this process,” said Kim Riddle, an agency spokeswoman.

The Maritime Administration solicited bids for the ships in early June. A deadline for bidding was July 20.

The agency has owned the Alakai and Huakai since September when a foreclosure auction outside the federal courthouse in Norfolk, Va., failed to attract a buyer willing to pay anything close to what the agency spent to help finance construction of the vessels.

The agency provided two loan guarantees totaling roughly $140 million toward the $190 million construction cost of the two ships for the Superferry. At the foreclosure auction no one bid more than $25 million per ship, so the agency kept the vessels.

The Superferry launched service in August 2007 with the Alakai between Oahu and Maui, representing the tip of what was envisioned to become a new interisland ocean highway served by vessels capable of carrying 836 passengers and 282 cars at speeds approaching 40 knots, or 46 mph. But the venture was shut down in March 2009 after service problems and a legal ruling that said the ferry should have produced an environmental impact study. The Huakai was never put into service.

After filing for bankruptcy in May 2009, the Superferry turned over the ships to the Maritime Administration. The agency paid its roughly $140 million obligation to investors and lenders, and formally repossessed the ships.