An international criminal inquiry into the 2014 downing of Flight MH17 over eastern Ukraine revealed Wednesday that a BUK missile which brought down the plane was transported from Russia.

Here are the main findings of the inquiry carried out by the Joint Investigation team (JIT), led by Dutch prosecutors with teams from Australia, Belgium, Malaysia and Ukraine.

- The weapon -

The JIT said it has "irrefutable evidence to establish that on 17 July 2014, Flight MH17 was shot down by a BUK missile from the 9M38-series." Some 298 people were killed when the Malaysia Airlines plane on a routine flight from Amsterdam to Kuala Lumpur was blown out of the skies over eastern Ukraine.

It made this determination by dismantling various types of BUK, a Russian-made ground-based air defence system, and comparing them to metal parts recovered from the crash site.

Investigators also ruled out alternative scenarios that the disaster was caused by an accident or a terror attack. And according to radar data, no other planes were in the area which could have shot it down.

- Where did the missile come from? -

Using photos, videos and intercepted phone conversations, the investigators retraced the missile system's route which they say originated in Russia.

"The system was transported from Russian territory into eastern Ukraine and was later transported on a white Volvo truck with a low-boy trailer. The truck was escorted by several other vehicles and by armed men in uniform," the inquiry concludes.

An intercepted telephone conversation said to be between two Russian-speaking men fighting on the side of the separatists suggests the launcher crossed the border on the night between July 16 and 17.

The wiretapped conversation intercepted on Wednesday, July 16, 2104 at 7:09 pm records one man, identified as Nikolayevich, saying he doesn't know if "his men can hold" and asking if he can "receive a BUK in the morning... that'd be good. If not things will go totally fucked up".

"If you need ... we'll send it over to your area," the other man, called Sanych, replies.

- The launch site -

The final destination of the BUK-TELAR launch system was farmland near Pervomaiskyi. Investigators said that at the time the field was in rebel-held territory.

Witnesses told the investigators they had seen "a plume of smoke, the BUK-TELAR at the launch site in Pervomaiskyi, and the missile right after it had been launched."

Multiple witnesses had also photographed the condensation trail of the missile and its movement.

"After the BUK missile had been fired, the BUK-TELAR initially drove off under its own power. A short time later it was reloaded onto the Volvo truck and transported back to the Russian border. During the night, the convoy crossed the border into the territory of the Russian Federation," the inquiry says.

- The perpetrators -

Investigators did not name any suspects, but revealed they have identified about 100 people "who can be linked to the downing of MH17 or the transport of the BUK-TELAR."

It is also probing the chain of command, and has extended the investigation to January 2018.

"Who gave the order to bring the BUK-TELAR into Ukraine and who gave the order to shoot down flight MH17? Did the crew decide for themselves or did they execute a command from their superiors? This is important when determining the offences committed by the alleged perpetrators," the inquiry states in its report.

The JIT team has put a number of intercepted phone conversations on its website www.jitmh17.com and is asking people who recognise the voices to come forward with information.