France launched a hunt for more wreckage from the ill-fated MH370 plane off Reunion island on Friday in a fresh effort to shed light on one of aviation's biggest mysteries.

The tiny French Indian Ocean territory has been under intense scrutiny since a beach cleaner found a washed-up wing part last week, which Malaysian Prime Minister Najib Razak later declared was part of the Boeing 777 that mysteriously vanished 17 months ago.

The flaperon is currently being examined by experts in France for clues as to the last moments of the Malaysia Airlines aircraft that inexplicably veered off course en route from Kuala Lumpur to Beijing, and there are hopes that Reunion may yield more debris.

In nearby Mauritius, authorities are also searching for any possible plane parts that may have landed on their shores.

Dominique Sorain, the top government official in Reunion island, told reporters that a military transport plane was patrolling the seas off the coast and a ship had also departed before being forced to return due to bad weather.

He added that helicopters would also be used, as would soldiers and policemen who will patrol the eastern part of the island where the flaperon was discovered.

"This... will last a week, after which we will draw our first conclusions," Sorain said.

Since the discovery of the two-meter-long flaperon last week, people on the island have come forward with countless objects they think may look like plane parts.

Sorain said some of these objects had been placed under seal to wait for experts to determine whether they really are bits of aircraft or not.

Malaysian Transport Minister Liow Tiong Lai said Thursday that more possible MH370 objects -- aircraft seat cushions and windows -- had been discovered on Reunion island, but that any link "had to be verified by the French authorities."

A French judicial source however said French investigators had not received any new items.

The Boeing 777 disappeared on March 8 last year, sparking the largest search operation in history, now focused on the southern Indian Ocean based on satellite data hinting at the plane's path.

Australian authorities, which are leading the search, expressed renewed confidence that they were looking in the right area.

"The finding of this piece of wing gives us hope that we are searching in the right location, given the tides and currents and drift patterns," Foreign Minister Julie Bishop told Australian television from Malaysia.

French prosecutors involved in the analysis of the flaperon have however been more cautious, saying only that there was a "very high probability" it came from the Boeing 777.

But Liow said on Thursday that certain characteristics of the wing part, including its paint, matched MH370 maintenance records -- backing up Najib's announcement that it was part of the plane.

Najib's televised statement was not universally welcomed by relatives of the 239 people on board the jet, with some expressing skepticism and fresh criticism of officials' handling of the disaster.

"There is no conclusive evidence that this part belongs to the Boeing," said Ghislain Wattrelos, who lost his wife and two of his children on the flight.

"It's not 100 percent (sure) like the Malaysian prime minister said."

Chinese relatives of passengers aboard MH370 marched to Malaysia's embassy in Beijing on Friday, some demanding to be taken to Reunion.

"We want to go to the island and see the truth," said Lu Zhanzhong, whose son was on the plane.

Some anguished family members nevertheless said any first concrete proof of the plane's fate would help bring closure.

"We've had 17 months of nothing... so actually finding something is the first step towards pinpointing where it is," Sara Weeks, the sister of MH370 passenger Paul Weeks, told the Fairfax New Zealand media group.

Analysts call the flaperon find a clear step forward by eliminating theories that the plane might have landed somewhere, and confirming the search was roughly on the right track.

But they caution that only by locating a crash site and recovering the black box are authorities likely to help solve the mystery, unless new evidence emerges elsewhere.

It is hoped that more detailed examination of the wing part in the coming days may indicate how it detached from the aircraft and whether it showed traces of an explosion or fire.