(CNN) -- Bones found last week near where Steve Fossett's plane crashed in eastern California's Sierra Nevadas are those of the adventurer, authorities said Monday.
Fossett, seen here with his wife, Peggy, disappeared after a solo flight in 2007.
Testing at California's state crime lab determined that "two large bones" recovered Wednesday matched Fossett's DNA, a spokeswoman for the Madera County Sheriff's Department in California said.
Madera County Sheriff John Anderson said last week that confirmation that the bones were Fossett's would allow authorities to conclude with certainty that Fossett is dead.
Fossett was last seen on the morning of September 3, 2007, when he took off from the Flying-M Ranch outside Minden, Nevada. He was scouting locations for an attempt to break the land-speed record in a rocket-propelled car.
Searchers found the bones, Fossett's driver's license, a pair of shoes and a $100 bill on Wednesday, Anderson said last week. The discovery site was a little more than a half-mile from where Fossett's plane wreckage was found on October 1 in a remote area of the Sierra Nevadas at an altitude of 10,000 feet. See map showing takeoff site, crash site »
The site of Wednesday's discovery also is about a quarter-mile from where a hiker reported finding two aviation identification cards with Fossett's name and $1,000 in cash in late September, Anderson said.
Animal chew marks were found on the driver's license and the shoes, Anderson said. He said the marks indicate that "animals possibly [moved] the body."
Previous DNA tests on what were believed to be bone fragments at and near the crash site showed that the fragments weren't human remains, Anderson said.
The National Transportation Safety Board has been investigating the wreck.
Fossett made his money in the financial services industry but became renowned for his daredevil exploits. Read about Fossett's milestones »
Fossett was the first person to circle the globe solo in a balloon, in 2002, and the first to fly a plane around the world solo without refueling three years later. He also set world records in round-the-world sailing and cross-country skiing.
All About Steve Fossett • U.S. National Transportation Safety Board
According to California's Madera County Sheriff's office, DNA tests performed on bones found at the site of a plane crash in October, are confirmed to be those of adventurer Steve Fossett.

Steve Fossett in 2006 Image:  NASA/Kim Shiflett
The last known whereabouts of Fossett was on September 3, 2007. He had taken a small plane from a ranch in Minden, Nevada to search for a site to try and break the land-speed record. He had not been seen since and authorities feared his plane had crashed and he had died.


"A California Department of Justice Forensics lab has determined that items containing DNA - discovered last week - match James Stephen Fossett's DNA," said the Sheriff's department in a statement.

Items were found last week at his crash site in the Sierra Nevada Mountains along with his identification card, a one-hundred dollar bill, and a pair of shoes. A few bones believed to be his were found a short distance from the crash. Teeth marks were found in his ID card, leaving authorities to believe his body was moved by animals. Forensic investigators say Fossett would have died immediately on impact.

In September, a hiker found other identification cards and money just under a mile from where authorities later found the wreckage of his plane on October 1.