Dutch prosecutors said Friday they need to know where a missile that may have shot down flight MH17 was fired from in eastern Ukraine before criminal charges could be laid.

"When we know from where it was fired, then we can find out who controlled that area," and possibly prosecute, Dutch chief investigator Fred Westerbeke told journalists in Rotterdam.

"The most likely scenario was that the plane was shot down from the ground," he said.

Dutch authorities have taken the lead in the criminal probe into what brought down Malaysia Airlines flight MH17 over conflict-torn Ukraine on July 17, killing all 298 on board, most of them Dutch.

Westerbeke said that they had not yet obtained US satellite photos of areas from which a missile might have been launched.

"We will get them," Westerbeke said, adding that it was a "long process".

An initial report by a Dutch air safety probe into the crash released on Tuesday said that the plane was struck by numerous "high-energy objects".

The report ruled out pilot error or mechanical failure, leaving shooting down from the ground or from the air as well as a terrorist bombing as the only other scenarios.

Kiev and the West have accused separatists of shooting it down with a surface-to-air BUK missile supplied by Moscow.

Moscow and the rebels deny this and point the finger at Kiev.

Privileging the missile strike theory, investigators are examining "around 25" pieces of metal found in some of the bodies, said Patricia Zorko of the Dutch national police.

"Now we need to find out if they come from inside the plane or is this something that came from outside the plane," Zorko told journalists.

Intercepted telephone conversations between separatists allegedly talking about shooting down the plane have not yet been authenticated.

"We are studying the intercepted telephone call," Zorko said of one of the conversations.

"The conversation is between rebels who allegedly shot down the plane, but we really need to authenticate it," she said.

The Netherlands lost 193 citizens, Malaysia lost 43 and Australia 27 on the doomed flight from Amsterdam to Kuala Lumpur.

So far 193 crash victims of the crash have been identified.

An international investigation team involving police and prosecutors from several countries including the Netherlands, Australia, Ukraine and Belgium as well as, to a lesser extent, Malaysia, has been set up, with over 100 investigators working on the probe.

Investigators have made, received or found about 20,000 pictures and 750 videos, which they are studying, said Zorko.