An American who discovered an aircraft part in Mozambique that may be from missing Malaysia Airlines Flight 370 said Thursday that he initially thought it was from a much smaller plane.

Blaine Gibson, who has been searching the region's beaches for the debris, said in an interview with The Associated Press that a boat operator who took him to a sandbank named Paluma called him over after seeing a piece of debris with "NO STEP" written on it.

"It was so light," Gibson said.

He said the discovery happened after he decided to go "somewhere exposed to the ocean" on the last day of a trip to the Mozambican coastal town of Vilankulo.

"At first, all I found were usual beach detritus — flip flops, cigarette lighters. Then 'Junior' called me over," said Gibson, using the nickname of the boat operator.

The location of the debris turned up in a spot that matches investigators' theories about where wreckage from the plane would have ended up, according to Australian officials.

The plane is believed to have crashed somewhere in a remote stretch of the southern Indian Ocean far off Australia's west coast and about 6,000 kilometers (3,700 miles) to the east of Mozambique. But authorities have long predicted that any debris from the plane that isn't on the ocean floor would eventually be carried by currents to the east coast of Africa.

Gibson, from Seattle, said the piece of debris that he discovered is in the hands of civil aviation authorities in Mozambique, and that he expects it to be transferred to their Australian counterparts.

"It's important to keep it in perspective," Gibson said. "This is about the families of the 239 victims, who haven't seen their relatives for two years now."

Photos of the debris appear to show the fixed leading edge of the right-hand tail section of a Boeing 777, said a U.S. official, who spoke on condition of anonymity because he wasn't authorized to speak publicly. Flight 370 is the only known missing 777.

Australian Transport Minister Darren Chester said Thursday the location of the debris in Mozambique matches investigators' drift modeling and would therefore confirm that search crews are looking in the right part of the Indian Ocean for the main underwater wreckage. Malaysian Transport Minister Liow Tiong Lai also said the location of the debris lines up with investigators' predictions.

People who have handled the part, called a horizontal stabilizer, say it appears to be made of fiberglass composite on the outside, with aluminum honeycombing on the inside, the U.S. official said.

The Australian Transport Safety Bureau, which is running the search for the plane in remote waters off Australia's west coast, said the part is expected to be transported to Australia for examination.

Malaysian representatives from the nation's Civil Aviation department and Malaysia Airlines were heading to Mozambique to discuss the find, Liow said.

From the pictures shown, it's high probability that the plane debris is from Boeing 777, Liow told reporters. He did not know how long it would be before the part was sent to Australia. Meanwhile, authorities in Mozambique were searching the area where it was found for other potential debris, Liow said.

Australian officials have seen photographs of the part and have been in communication with Gibson, said Dan O'Malley, a spokesman for the Australian Transport Safety Bureau.

"We're aware of these reports that debris has been found in Mozambique," O'Malley said. "We're working with officials in Mozambique and Malaysia to investigate."

Australia will work with Malaysian investigators to examine the object once it arrives in Australia, he said. The ATSB hasn't made any determinations yet about the potential origins of the debris.

"We have to wait until we have the actual debris examined," O'Malley said. "We're not going to draw conclusions from the photos."

Some have expressed skepticism that the part could be from the missing aircraft because it appears to be remarkably clean and free of sea life — unlike the barnacle-encrusted wing part that washed ashore on the French island of Reunion last year. That part, known as a flaperon, remains the only confirmed trace of Flight 370.

But Charitha Pattiaratchi, an oceanographer with the University of Western Australia, said if the part was discovered on a sandbank, the motion of the waves pushing it against the abrasive sand may have shaved any sea life off it.

"If somebody actually found it in the middle of the ocean while they were sailing and picked it up, I would say, 'Well, that should have some barnacles,'" he said. "But if it's been on a beach, it's basically been sandblasted."

Also, the part appears to be very flat and barnacles need something to grip, he said.

Last year, Pattiaratchi met with Gibson. Pattiaratchi has used computer modeling to predict where floating debris might end up and Gibson wanted to get Pattiaratchi's opinion on where to look. Pattiaratchi's models showed it would likely end up around Madagascar or Reunion Island, and possibly in the Mozambique Channel.

Flight 370 disappeared on March 8, 2014, while flying from Kuala Lumpur to Beijing. Authorities who scrutinized data exchanged between the plane's engine and a satellite determined that after veering sharply off course, the jetliner continued on a straight path across the Indian Ocean, leading them to believe that it flew on autopilot for hours before running out of fuel and crashing into the water.

Australia has led a multinational search effort, which also includes the Malaysian and Chinese governments. But no trace of the passengers, their luggage or even things designed to float, such as life jackets, has been discovered.

With authorities unable to find the plane and its "black box" flight data and cockpit voice recorders, investigators are no closer than they were two years ago to discovering the cause of the aircraft's disappearance.

With the search tentatively scheduled to wrap up in June, Flight 370 may become one of aviation's great unsolved mysteries.

Liow said it is premature to say whether the search could be expanded beyond June. Ministers from Malaysia, Australia and China will meet in Kuala Lumpur in June to assess the situation and listen to experts' views, Liow said.

An international investigation team looking into the disappearance will issue an interim statement on March 8, Liow said.