San Francisco - A new search was launched Wednesday for missing and presumed-dead adventurer Steve Fossett after hikers in the Sierra Nevada Mountains discovered ID cards, clothes and some 1,000 dollars in cash that appeared to belong to him, authorities said.

Ian Gregor, a spokesman for the Federal Aviation Administration in Los Angeles, confirmed that the copy of a pilot's license he had received matched Fossett's details.

"The certificate number and date of issue on the document in the photo matches the information we have for Mr Fossett in our database," he said.

Other information, including Fossett's date of birth and his address, also matched, he said.

The items were found by ski-shop owner Preston Morrow near the remote recreation town of Mammoth Lakes close to the California- Nevada border about 500 kilometres north of Los Angeles. He handed them over to the police after an approach to the Fossett family was rebuffed.

The new information was enough to reconvene a search that was halted over six months ago after an exhaustive search by air and ground failed to discover any trace of Fossett, 63, or the light plane that he was flying when he disappeared in September 2007. The previous searches had not concentrated on the area around Mammoth Lakes, where the recently discovered artifacts were found.

Fossett's widow, Peggy Fossett said she hoped the new discovery would help bring closure to her husband's disappearance.

"I am aware of the search underway for my husband, Steve Fossett, in the Mammoth Lakes area of Madera and Mono counties, California, following the discovery by a hiker of personal items that appear to belong to my husband," she said in the statement. "I am hopeful that this search will locate the crash site and my husband's remains. I am grateful to all of those involved in this effort."

Fossett disappeared as he was apparently trying to find a site to attempt an assault on the world land speed record. A billionaire financial trader Fossett set 116 records in sailboats, powered aircraft, balloons, airships and gliders. He also swam the English Channel, drove in the 24 Hours of Le Mans car race, competed in Hawaii's Ironman Triathlon, sailed solo across both the Atlantic and Pacific oceans, climbed Argentina's 23,000-foot Aconcagua peak and competed in Alaska's Iditarod Trail sled dog race.