Australia and the Netherlands announced on Friday they would send military police forces to the area in eastern Ukraine where a Malaysia Airlines jet was shot down last week. They also prepared to seek approval from the United Nations Security Council, of which Australia is a rotating member, for an armed mission to secure the crash site.

Australia said it was flying in one hundred police and some defense force personnel in addition to the ninety officers already waiting in London for approval from Ukraine’s parliament to be deployed in the country.

The Netherlands is sending forty unarmed military police officers to aid forensic experts who arrived in Ukraine earlier this week to investigate the crash.

Prime Minister Mark Rutte told lawmakers on Friday it was “far from certain” armed forces would join the contingent although Dutch media reported that soldiers of the elite Air Maneuver Brigade had been called back from leave while commandos were pulled out of Mali.

Australia also sent members of the Special Air Service Regiment to Hereford, England, suggesting a joint special operations mission was imminent.

220 out of the 298 passengers and crew who died in the plane crash were Australian or Dutch nationals.

On Friday afternoon, the third airlift carrying the bodies of the deceased was due to arrive at Eindhoven’s military airport. Two days earlier, when Australian and Dutch military transport aircraft brought the first bodies to the Netherlands, the European country observed a day of national mourning.

While Ukraine’s government promised to fully cooperate with the investigation, armed rebels in the east of the country, who likely brought down the airliner, mistaking it for an Ukrainian military plane, ransacked the crash site and initially stopped monitors from the Organization for Security and Cooperation in Europe from inspecting the area.

Russia, which supports the separatist uprising in eastern Ukraine, said on Thursday it would cooperate with the Dutch investigation into the plane crash — but also denied it had supplied the rebels with a missile launcher to shoot down a commercial jetliner at cruising altitude.

Western countries have ridiculed Russian media’s assertions that the Malaysia Airlines flight was shot down by Ukrainian soldiers who supposedly mistook it for President Vladimir Putin’s personal jet.

One separatist leader also told the Reuters news agency on Wednesday that the rebels did possess the Buk missile system Western countries believe was used to shoot down the commercial plane and that it could have been sent to Russia to remove proof of its presence.

Before the Malaysian plane was shot down, rebels had boasted of obtaining Buk missiles. But since the crash, the breakaway People’s Republic of Donetsk — which seeks to join the Russian Federation — has denied ever having possessed such weapons.

In a phone call on Thursday, American president Barack Obama and the Netherlands’ Mark Rutte agreed on the need to impose more sanctions on Russia as it continued to support the uprising in Ukraine. “Instead of deescalating the situation, they agreed that all evidence indicates Russia is still arming and supplying separatists who continue to engage in deadly acts of aggression against Ukrainian armed forces,” a White House statement said.