(CNN) Malaysia's Transport Ministry said Thursday that more plane parts have washed up on the same remote French island as a wing part that is believed -- with varying degrees of certainty -- to be from missing Malaysia Airlines Flight 370.

The new items found on Reunion Island in the Indian Ocean include pieces of windows, seat cushions and aluminum, Malaysian officials said. But they added that it's unclear whether the objects, which still need to be verified by French authorities, are from MH370.

"The team told us they have managed to collect more debris on the island and we have handed it over to the authorities in France," Malaysian Transport Minister Liow Tiong Lai told reporters. "A plane window and some aluminum foil ... there are many items."

French officials on Reunion and in Paris, however, haven't reported any new plane debris.

And an Australian agency helping coordinate the search for the missing airliner said Wednesday, the day before Malaysia announced the discovery of new items, that there was no indication so far of any more aircraft debris.

"A great deal of additional material has been handed over to the police" on Reunion, Australia's Joint Agency Coordination Centre said in a statement. "While this is being examined, so far none of it appears to have come from an aircraft."

The Australians are in charge of the underwater search for Flight 370 in the eastern Indian Ocean, thousands of miles from Reunion. Malaysia has overall responsibility for the investigation into the loss of the plane.

Although Malaysian Prime Minister Najib Razak announced that the wing part found last week, which is called a flaperon, is certainly from MH370, other officials have expressed more caution and say that more testing is needed.

Less than an hour after the Prime Minister's statement, Paris Deputy Prosecutor Serge Mackowiak used slightly less definitive language. He said that there were "very strong presumptions" that the debris from Reunion is from MH370, but that absolute certainty was not yet possible.

Malaysian officials provided more details later Thursday of what makes them sure it was from the missing jet, including a serial number that matches technical records.

The Boeing 777, carrying 239 people, disappeared on a flight from Kuala Lumpur, Malaysia, to Beijing on March 8, 2014.

The families

Some families of those on board have said they are angry, frustrated and bewildered by what they've been told.

Photos: Remembering the passengers of MH370 Photos: Remembering the passengers of MH370 There is still no way to know for sure why Flight MH370 ended, but we are learning more about the lives of those on board. CNN is remembering them through snapshots shared with us. Hide Caption 1 of 12 Photos: Remembering the passengers of MH370 Rodney and Mary Burrows were looking forward to becoming first-time grandparents after their return home to Australia. Hide Caption 2 of 12 Photos: Remembering the passengers of MH370 Australians Catherine and Robert Lawton were traveling with friends on vacation when the flight disappeared. Hide Caption 3 of 12 Photos: Remembering the passengers of MH370 Paul Weeks was traveling to Mongolia for a new job as an engineer. His wife says Paul left behind his watch and his wedding ring before the trip, in case anything happened to him while he was away. Anderson spoke with Paul's brother & sister who said they are coping by spending time together as a family. Hide Caption 4 of 12 Photos: Remembering the passengers of MH370 Chandrika Sharma, left, was on Flight 370; her daughter Meghna and husband K.S. Narendran wait patiently, trying to manage their anxiety and longing for her return. Hide Caption 5 of 12 Photos: Remembering the passengers of MH370 Muktesh Mukherjee and Xiaomo Bai had been vacationing in Vietnam and were on their way home to their two young sons in Beijing. Hide Caption 6 of 12 Photos: Remembering the passengers of MH370 76-year-old Liu Rusheng, an accomplished calligrapher and one of the oldest passengers on the flight, was in Malaysia to attend an art exhibition with his wife. Hide Caption 7 of 12 Photos: Remembering the passengers of MH370 Teens Hadrien Wattrelos and Zhao Yan are shown in a photo on Wattrelos' Facebook page. The photo is captioned, simply, "I love you," in French. Hide Caption 8 of 12 Photos: Remembering the passengers of MH370 Firman Chandra Siregar, 24, studied electrical engineering in Indonesia and was on his way to Beijing on board Flight 370 to start a new job at an oil company. Hide Caption 9 of 12 Photos: Remembering the passengers of MH370 Patrick Francis Gomes, center, was the in-flight supervisor for the missing plane. His daughter describes him as a quiet person with a sense of humor. Hide Caption 10 of 12 Photos: Remembering the passengers of MH370 Ch'ng Mei Ling, a Malaysian citizen who lives in Pennsylvania, is a process engineer at a chemical company. Hide Caption 11 of 12 Photos: Remembering the passengers of MH370 We do not have photos of all 239 passengers, but we wanted to remember that there are loved ones around the world missing them right now. View CNN's complete coverage of Flight 370. Hide Caption 12 of 12

"I was left somewhat confused and, frankly, a little angry and dismayed," said K.S. Narendran, whose wife was one of the passengers

"I didn't hear facts. I didn't hear the basics. I heard nothing," he said, "and so it leaves me wondering whether there is a foregone conclusion and everyone is racing for the finish."

The families of Chinese passengers, the most numerous nationality on the flight, were also unsatisfied.

"I don't believe this. I don't!" said Xu Jinghong, whose mother was on board Flight 370. "I am furious and I think this announcement is very irresponsible."

Chinese families said last week they wanted "confirmation of 100% certainty" from authorities that the part was from MH370. But the differing Malaysian and French statements appeared to leave them with room for uncertainty.

Other relatives said that the flaperon was only a small piece of a much larger puzzle.

"It's not the end," Jacquita Gonzales, wife of crew member Patrick Gomes, told reporters. "Although they found something, you know, it's not the end. They still need to find the whole plane and our spouses as well. We still want them back."

Lim Khim Fatt's husband was on the flight.

"There's a lot of questions that haven't been answered yet," she said.

A history of family skepticism

Some families have long been skeptical and disappointed by how Malaysian officials have handled looking for and delivering news about the missing plane.

The Malaysian government has been wrong several times before. On March 17, for example, Malaysian authorities publicly confirmed the final words from the cockpit as "All right, good night."

The innocuous bit of radio banter became yet another headache for investigators when, after days of prodding from reporters and family members, they released a transcript showing the final words were actually, "Good night Malaysian three seven zero."

Malaysian military radar captured signatures of what was believed to have been Flight 370, but it wasn't immediately noticed.

While the radar data was the key reason for expanding the search west of Malaysia, it took officials until March 11 -- three days after the disappearance -- to explain why they were looking so far off the plane's expected course. All the while, search efforts continued in places where data showed it could not have been -- the Gulf of Thailand and the South China Sea.

A report issued a month after the plane's disappearance also highlighted snafus in crucial communication between air traffic control centers and Malaysia Airlines on the morning Flight 370 disappeared.

The investigation

Najib, the Malaysian Prime Minister, didn't go into any detail in his statement early Thursday on what Malaysian officials believe provides the conclusive link between the flaperon found on Reunion and MH370.

But Malaysia's Transport Ministry provided more information later in the day, saying that a serial number on the wing part matches Malaysia Airlines' technical records.

The ministry said it found matches for a maintenance seal and paintwork on the flaperon.

Photos: MH370 debris discovered on Reunion Island Photos: MH370 debris discovered on Reunion Island Debris discovered on the island of Reunion, a French territory in the Indian Ocean, was confirmed to be from Malaysia Airlines Flight 370, Malaysian Prime Minister Najib Razak said August 5. The plane disappeared in March 2014 with 239 people on board. Hide Caption 1 of 5 Photos: MH370 debris discovered on Reunion Island French police officers carry the plane debris on July 29. Experts say the metallic object may be a piece of a moving wing surface, known as a flaperon, from a Boeing 777. Hide Caption 2 of 5 Photos: MH370 debris discovered on Reunion Island Police officers inspect debris on July 29. Hide Caption 3 of 5 Photos: MH370 debris discovered on Reunion Island Another piece of debris resembles remnants of a suitcase. Hide Caption 4 of 5 Photos: MH370 debris discovered on Reunion Island Police carry debris on July 29. Hide Caption 5 of 5

Mackowiak, the Paris deputy prosecutor, had stopped short of announcing a definitive link.

Boeing officials have concluded that the part's technical features -- such as its color and the structure of its joints -- confirm that it's from a 777 aircraft, he said.

Drawing on documentation provided by Malaysia Airlines, experts also identified "common technical characteristics" between the flaperon found on Reunion and that of Flight 370, Mackowiak said.

His more cautious language highlights the complex, multinational nature of the investigation into what happened to MH370.

Malaysia Airlines said in a statement that the confirmation announced by Najib, which it described as "a major breakthrough," had been made jointly by French, Malaysian, Chinese and Australian officials.

But a source close to the investigation told CNN that French and U.S. experts examining the flaperon have not yet found anything that would definitively link it to Flight 370. The American officials involved are from the National Transportation Safety Board.

While it is expected that the wing part will eventually be matched to MH370, the source said that there was so far nothing precise enough for 100% confirmation.

The next steps

The analysis of the flaperon will continue at a specialized lab near Toulouse, France.

"The experts are carrying out their work promptly in order to provide complete and reliable information as soon as possible to the victims' families," Mackowiak said.

Photos: The search for MH370 Photos: The search for MH370 Two years after Malaysia Airlines Flight 370 went missing, a relative of one of the passengers burns incense in Beijing on March 8, 2016. Flight 370 vanished on March 8, 2014, as it flew from Kuala Lumpur, Malaysia, to Beijing. There were 239 people on board. Hide Caption 1 of 43 Photos: The search for MH370 On July 29, police carry a piece of debris on Reunion Island, a French territory in the Indian Ocean. A week later, authorities confirmed that the debris was from the missing flight. Hide Caption 2 of 43 Photos: The search for MH370 Staff members with the Australian Transport Safety Bureau examine a piece of aircraft debris at their laboratory in Canberra, Australia, on July 20. The flap was found in June by residents on Pemba Island off the coast of Tanzania, and officials had said it was highly likely to have come from Flight 370. Experts at the Australian Transport Safety Bureau, which is heading up the search for the plane, confirmed that the part was indeed from the missing aircraft. Hide Caption 3 of 43 Photos: The search for MH370 In late February, American tourist Blaine Gibson found a piece of plane debris off Mozambique, a discovery that renewed hope of solving the mystery of the missing flight. The piece measured 35 inches by 22 inches. A U.S. official said it was likely the wreckage came from a Boeing 777, which MH370 was. Hide Caption 4 of 43 Photos: The search for MH370 Relatives of the flight's passengers console each other outside the Malaysia Airlines office in Subang, Malaysia, on February 12, 2015. Protesters had demanded that the airline withdraw the statement that all 239 people aboard the plane were dead. Hide Caption 5 of 43 Photos: The search for MH370 A police officer watches a couple cry outside the airline's office building in Beijing after officials refused to meet with them on June 11, 2014. The couple's son was on the plane. Hide Caption 6 of 43 Photos: The search for MH370 Members of the media scramble to speak with Azharuddin Abdul Rahman, director general of Malaysia's Civil Aviation Department, at a hotel in Kuala Lumpur, Malaysia, on May 27, 2014. Data from communications between satellites and the missing flight was released the day before, more than two months after relatives of passengers said they requested it be made public. Hide Caption 7 of 43 Photos: The search for MH370 Operators aboard the Australian ship Ocean Shield move Bluefin-21, the U.S. Navy's autonomous underwater vehicle, into position to search for the jet on April 14, 2014. Hide Caption 8 of 43 Photos: The search for MH370 A member of the Royal New Zealand Air Force looks out of a window while searching for debris off the coast of western Australia on April 13, 2014. Hide Caption 9 of 43 Photos: The search for MH370 The HMS Echo, a vessel with the British Roya; Navy, moves through the waters of the southern Indian Ocean on April 12, 2014. Hide Caption 10 of 43 Photos: The search for MH370 A Royal Australian Air Force AP-3C Orion, on a mission to drop sonar buoys to assist in the search, flies past the Australian vessel Ocean Shield on April 9, 2014. Hide Caption 11 of 43 Photos: The search for MH370 A relative of a missing passenger cries at a vigil in Beijing on April 8, 2014. Hide Caption 12 of 43 Photos: The search for MH370 Australian Defense Force divers scan the water for debris in the southern Indian Ocean on April 7, 2014. Hide Caption 13 of 43 Photos: The search for MH370 A towed pinger locator is readied to be deployed off the deck of the Australian vessel Ocean Shield on April 7, 2014. Hide Caption 14 of 43 Photos: The search for MH370 A member of the Royal New Zealand Air Force looks at a flare in the Indian Ocean during search operations on April 4, 2014. Hide Caption 15 of 43 Photos: The search for MH370 On March 30, 2014, a woman in Kuala Lumpur prepares for an event in honor of those aboard Flight 370. Hide Caption 16 of 43 Photos: The search for MH370 The sole representative for the families of Flight 370 passengers leaves a conference at a Beijing hotel on March 28, 2014, after other relatives left en masse to protest the Malaysian government's response to their questions. Hide Caption 17 of 43 Photos: The search for MH370 A member of the Royal Australian Air Force is silhouetted against the southern Indian Ocean during the search for the missing jet on March 27, 2014. Hide Caption 18 of 43 Photos: The search for MH370 Flight Lt. Jayson Nichols looks at a map aboard a Royal Australian Air Force aircraft during a search on March 27, 2014. Hide Caption 19 of 43 Photos: The search for MH370 People in Kuala Lumpur light candles during a ceremony held for the missing flight's passengers on March 27, 2014. Hide Caption 20 of 43 Photos: The search for MH370 Malaysian Prime Minister Najib Razak, center, delivers a statement about the flight on March 24, 2014. Razak's announcement came after the airline sent a text message to relatives saying it "deeply regrets that we have to assume beyond any reasonable doubt that MH 370 has been lost and that none of those onboard survived." Hide Caption 21 of 43 Photos: The search for MH370 Grieving relatives of missing passengers leave a hotel in Beijing on March 24, 2014. Hide Caption 22 of 43 Photos: The search for MH370 A passenger views a weather map in the departures terminal of Kuala Lumpur International Airport on March 22, 2014. Hide Caption 23 of 43 Photos: The search for MH370 A Chinese satellite captured this image, released on March 22, 2014, of a floating object in the Indian Ocean, according to China's State Administration of Science. It was a possible lead in the search for the missing plane. Surveillance planes were looking for two objects spotted by satellite imagery in remote, treacherous waters more than 1,400 miles from the west coast of Australia. Hide Caption 24 of 43 Photos: The search for MH370 Satellite imagery provided by the Australian Maritime Safety Authority on March 20, 2014, showed debris in the southern Indian Ocean that could have been from Flight 370. The announcement by Australian officials raised hopes of a breakthrough in the frustrating search. Hide Caption 25 of 43 Photos: The search for MH370 Another satellite shot provided by the Australian Maritime Safety Authority shows possible debris from the flight. Hide Caption 26 of 43 Photos: The search for MH370 A distraught relative of a missing passenger breaks down while talking to reporters at Kuala Lumpur International Airport on March 19, 2014. Hide Caption 27 of 43 Photos: The search for MH370 On March 18, 2014, a relative of a missing passenger tells reporters in Beijing about a hunger strike to protest authorities' handling of information about the missing jet. Hide Caption 28 of 43 Photos: The search for MH370 U.S. Navy crew members assist in search-and-rescue operations in the Indian Ocean on March 16, 2014. Hide Caption 29 of 43 Photos: The search for MH370 Members of the Chinese navy continue search operations on March 13, 2014. After starting in the sea between Malaysia and Vietnam, the plane's last confirmed location, search efforts expanded west into the Indian Ocean. Hide Caption 30 of 43 Photos: The search for MH370 A Vietnamese military official looks out an aircraft window during search operations March 13, 2014. Hide Caption 31 of 43 Photos: The search for MH370 Malaysian air force members look for debris near Kuala Lumpur on March 13, 2014. Hide Caption 32 of 43 Photos: The search for MH370 Relatives of missing passengers wait for the latest news at a hotel in Beijing on March 12, 2014. Hide Caption 33 of 43 Photos: The search for MH370 A member of the Vietnamese air force checks a map while searching for the missing plane on March 11, 2014. Hide Caption 34 of 43 Photos: The search for MH370 A Vietnamese air force plane found traces of oil that authorities had suspected to be from the missing Malaysia Airlines plane, the Vietnamese government online newspaper reported on March 8, 2014. However, a sample from the slick showed it was bunker oil, typically used to power large cargo ships, Malaysia's state news agency, Bernama, reported on March 10, 2014. Hide Caption 35 of 43 Photos: The search for MH370 A U.S. Navy Seahawk helicopter lands aboard the USS Pinckney to change crews on March 9, 2014, before returning to search for the missing plane in the Gulf of Thailand. Hide Caption 36 of 43 Photos: The search for MH370 Buddhist monks at Kuala Lumpur International Airport offer a special prayer for the missing passengers on March 9, 2014. Hide Caption 37 of 43 Photos: The search for MH370 Members of a Chinese emergency response team board a rescue vessel at the port of Sanya in China's Hainan province on March 9, 2014. Hide Caption 38 of 43 Photos: The search for MH370 The rescue vessel sets out from Sanya in the South China Sea on March 9, 2014. Hide Caption 39 of 43 Photos: The search for MH370 Malaysian Prime Minister Najib Razak, center, arrives to meet family members of missing passengers at the reception center at Kuala Lumpur International Airport on March 8, 2014. Hide Caption 40 of 43 Photos: The search for MH370 A relative of two missing passengers reacts at their home in Kuala Lumpur on March 8, 2014. Hide Caption 41 of 43 Photos: The search for MH370 Chinese police at the Beijing airport stand beside the arrival board showing delayed Flight 370 in red on March 8, 2014. Hide Caption 42 of 43 Photos: The search for MH370 Malaysia Airlines Group CEO Ahmad Juahari Yahya, front, speaks during a news conference at a hotel in Sepang on March 8, 2014. "We deeply regret that we have lost all contacts" with the jet, he said. Hide Caption 43 of 43

But he cautioned that he was unable to specify when the results of the ongoing analysis would be announced.

"On a forensic investigation, which is what's going on in France, you don't use the process of elimination and say, well, it must be a flap," said David Soucie, a CNN aviation analyst. "You have to have forensic proof, which is the samples from the paint, from the metal, to tie it specifically to the aircraft. That's what they're waiting for, and that's what they mean by 100% conclusive."

Experts have said that investigators may be able to glean clues from the wing debris about Flight 370's final moments before it is believed to have gone down in the southern Indian Ocean. Did it break apart in midair or hit the water intact?

But neither the French nor the Malaysians made any reference to that aspect of the analysis.

Australian Prime Minister Tony Abbott said Thursday that the Reunion Island discovery "suggests that for the first time we might be a little bit closer to solving this baffling mystery."

The remnants of a suitcase that were found near the flaperon on Reunion are being sent to a different French lab for examination, Mackowiak said.

The search

While a Malaysian official described apparently new plane debris that was found, a journalist on Reunion Island said, citing police, that no debris was reported or handed in Thursday. Police also say that nothing definitive has been turned in during the past week.

JUST WATCHED From disappearance to debris: CNN's coverage of MH370 Replay More Videos ... MUST WATCH From disappearance to debris: CNN's coverage of MH370 03:16

Additional air and water resources will be deployed off the coast of the island to look for debris, the French Defense Ministry announced late Thursday. A plane could be flying over the area as early as Friday morning.

French paramilitary operations will also be conducted, including foot patrols, helicopter and naval search missions, authorities said. The statement made no mention of any new plane parts being discovered.

It's anyone's guess whether many items from MH370 are likely to find their way to the remote island or others in the region.

"The problem is the only way for parts of the plane to get to Reunion Island is to continue to float," said Mary Schiavo, a CNN aviation analyst. "The flaperon could because there are spaces inside that part that could allow air to be trapped and for it to float."

But a lot of other potentially buoyant objects -- such as tennis shoes, bits of luggage and items from the plane's galley -- are likely to have become waterlogged and sunk after long months out in the ocean, she said.

The bigger, heavier parts of the aircraft are likely to have gone down into the depths more quickly.

Finding the plane's cockpit voice recorder and flight data recorder, as well as the cockpit itself, is likely to be investigators' best hope of unlocking the mystery of why the plane flew dramatically off course and lost communication with air traffic control.

Martin Dolan, chief commissioner of the Australian Transport Safety Bureau, said authorities have high confidence in the current search area.

"If the aircraft is in that area, which is highly probable, then we will find it," he said.