The Australian Transport Safety Bureau (ATSB) has officially confirmed that two of four pieces of plane debris found in the past few months are “almost certainly” from the missing MH370 plane.

Two damaged plane parts, one found in Mozambique in March and the other in South Africa in December 2015, were assessed as belonging to a Boeing 777, the same model as the lost Malaysian Airlines flight, according to the report published on Tuesday.

One of the pieces, a triangular piece of metal, was found by US blogger Blaine Alan Gibson on a sandbank near the coastal town of Vilankulo, just days before March 8, 2016 – the second anniversary of the disappearance.

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This part was identified as a horizontal stabiliser panel from the tail of the plane.

A panel used to control drag on an aircraft was found in South Africa. Photo: AAP

Marked with the words “NO STEP” in black paint, and with a single metallic fastener retained, the ATSB said it was clear where the part originated.

“All measurable dimensions, materials, construction and other identifiable features conformed to the Boeing drawings for the stabiliser panel,” the ATSB report said.

“The font and location of the stencil were not original from manufacture, however the stencilling was consistent with that developed and used by Malaysian Airlines.”

Transport minister Darren Chester flagged the contents of the report on March 24 before its official release.

Second piece also confirmed

The ATSB reported that maintenance records on stencilling and painting of a second debris piece, found by South African teenager Liam Lotter in late December 2015, indicated it was also “almost certainly” from MH370.

The flap track fairing segment, a part of the right wing that reduced drag, was identified by the markings 676EB.

The parts were two of four being analysed by the ATSB and Malaysian teams.

Two other parts – one found in South Africa and marked with a Rolls Royce logo, and a piece located on Rodrigues Island, in the Indian Ocean – arrived in Australia on April 13, but it was not clear if they were from MH370.

The South African part, found at a lagoon near Mossel Bay, could be from the engine’s cooling system.

“Based on early reports, there is a possibility of the piece originating from an inlet cowling of an aircraft engine,” Malaysian Transport Minister Liow Tiong Lai said, News Corp reported.

An American blogger found this tail part on the Mozambique coast. Photo: AAP

Meanwhile, a decorated metal object located on Rodrigues Island could be the first interior piece uncovered from the plane. Initial assessment of photos indicated it could be from the business class cabin.

‘There is no reason to believe they aren’t alive’

Despite the confirmation of the parts’ origins, the families of 154 Chinese people onboard reaffirmed the belief their loved ones were alive.

“There is no reason to believe MH370 crashed in the Southern Indian Ocean and reason to believe in a wholesale attempt at deception,” they said in a statement, citing proof they said showed data provided by authorities was incorrect.

“An extensive surface search and ocean floor search have found no supporting evidence MH370 crashed in the Southern Indian Ocean.

“We believe our missing loved ones may still be alive.”

A search of the ocean floor was scheduled to terminate in mid-2016, unless new information was uncovered.

Until Thursday, just one piece of debris, a wing flaperon, had been uncovered from the plane after it disappeared without a trace.

The wing part washed up on the coast of Reunion Island in July 2015.