The Dutch cabinet on Sunday ruled out sending a military mission to Ukraine to secure the area where a commercial airliner carrying 193 passengers from the Netherlands was shot down last week. But it left open the possibility of arming military police who were dispatched on Friday to support an investigation into the plane crash.

“We must simply ascertain that a military mission would lead to escalation,” Prime Minister Mark Rutte told reporters after consulting with his ministers in The Hague. That would “get in the way” of what is still the Netherlands’ priority, he added — “repatriating the victims.”

On Saturday, the fourth airlift carrying bodies of the deceased arrived at Eindhoven’s military airport. Three days earlier, when Australian and Dutch military transport aircraft brought the first bodies to the Netherlands, where they are due to be identified, the country observed a day of national mourning.

Dutch media had speculated that a special forces mission was being prepared to secure the crash site which sits between areas that are controlled by the Ukrainian government and militants who seek to secede from the country and join Russia. Members of the elite Air Maneuver Brigade had reportedly been called back from leave while commandos were pulled out of Mali.

Rutte said his government did intend to expand the number of investigators. Forty unarmed military police officers are already in Ukraine to aid a team of Dutch forensic experts there. Sixty more might be deployed soon.

Australia, which lost 27 nationals in the crash, and Malaysia, which lost 43 citizens, also sent security personnel.

Rutte said the Organization for Security and Cooperation in Europe, which has conflict monitors on the ground in Ukraine, is in talks with the separatists to allow the Dutch servicemen to carry weapons.

Western countries believe the rebels brought down the Malaysia Airlines jet, mistaking it for an Ukrainian military plane, with missiles that had been supplied by Russia. Russia denies this.

Soon after the plane came down, militants ransacked the crash site and denied OSCE monitors access to the area.

The Ukrainian government has promised to fully cooperate with the investigation and appeared to step up its offensive on Sunday, retaking the city of Sievierodonetsk, north of Luhansk, from the separatists. Heavy fighting was also reported in Torez, a city just east of the rebel stronghold Donetsk. Videos purporting to show Russian armored personnel carriers, infantry fighting vehicles and missile launchers moving across the border into eastern Ukraine were uploaded to YouTube.