A Florida deep-sea exploration firm with a track record of impressive underwater discoveries has found two colonial-era shipwreck sites in the English Channel, the company said Thursday.

Odyssey Marine Exploration filed documents in federal court seeking exclusive salvage rights to the sites. The documents request that the contents of the sites not be publicly revealed, the filings show.

Odyssey officials said in a press release that they do not know what ships they have found. But preliminary surveys showed cannon and other materials that may date back to colonial times, the company said.

"Odyssey believes that potentially valuable cargo may be located at or near the site," the company said in its filing.

Court filings indicate the newly discovered shipwreck sites to be in about 200 meters of water between 25 and 40 miles from the coast of England. Odyssey said it does not believe any country has a claim to the site and that it lies outside of territorial waters.

The company has done only a limited excavation and said it intends to do any further salvage or recovery under direction from the court.

The Tampa-based company made headlines last year when it announced it found 500,000 silver coins at a site in the Atlantic Ocean. Odyssey and the Spanish government have been fighting over that find ever since.

Odyssey announced earlier this year that it was excavating an unidentified shipwreck about 12 miles off the coast of North Carolina.

The firm also recently inked a deal with a production company to create an 11-part series for the Discovery Channel. The series could air in 2009, according to a press release.