Pro-Russian separatists have promised to cease fire for two to four days in eastern Ukraine to allow recovery work at the site where a Malaysian airliner carrying 298 people crashed, Russia's RIA news agency quoted a rebel leader as saying.
The announcement came as world leaders demanded an investigation into the cause of Thursday's crash, with the US and Germany saying there were indications the plane was shot down.
Emergency workers, police officers and even off-duty coal miners searched through wreckage and bodies scattered over a wide stretch of Ukrainian farmland, about 50km from the Russian border.
Al Jazeera's Scott Heidler, reporting from the scene near the village of Grabovo, said rescue workers were using sticks with white rags on the top to mark the location of bodies.
Ukraine, whose investigators have so far had no access to the area, has called for an international probe to determine who attacked the plane and insisted it was not its military. US intelligence authorities said a surface-to-air missile downed the plane, but could not say who fired it.
The Russian defence ministry said a Ukrainian radar station of surface-to-air missiles was operating on Thursday, but a spokesman for Ukraine's security council said no missiles in the country's armoury had been fired.
The rebels, who have risen up against Kiev's rule, will give unhampered access to the Organisation for Security and Cooperation in Europe, International Civil Aviation Organisation and Ukrainian detectives, said Andrei Purgin, a senior leader of the self-declared Donetsk People's Republic.
The announcement came as Ukraine closed the airspace over eastern regions where it is carrying out a security operation against separatists, the country's infrastructure ministry said.
The ministry said on its website that the airspace was completely closed over the eastern Donetsk and Luhansk regions where fighting has been raging and also partially prohibited flights above the neighbouring Kharkiv region.
Russian airlines have also limited their flights to Ukraine after the incident.
Flight MH17, en route from Amsterdam to Kuala Lumpur, was flying at about 33,000 feet [10km] over Ukraine when it was brought down. A majority of the passengers and crew on board were Dutch.
In a phone call with Mark Rutte, the Dutch prime minister, Russian President Vladimir Putin called for a "thorough and unbiased" investigation into the crash.
"The head of the Russian state underlined that the tragedy yet again highlighted the need for the swiftest peaceful solution to the acute crisis in Ukraine," the Kremlin said in a statement.
Despite the shooting down of several Ukrainian military aircraft in the area in recent months, including two this week, and renewed accusations from Kiev that Russian forces were taking a direct part, international air lanes had remained open.
Both sides in the conflict have accused each other of shooting down the Malaysian airlines airliner.
After the downing of several Ukrainian military aircraft in the area in recent months, including two this week, Kiev accused Russian forces of playing a direct role.
Liow Tiong Lai, Malaysian transport minister, said it would be an outrage against human decency if the plane was found to have been shot down.
"Should this be confirmed, it will contravene international law and be an outrage against human decency," Liow said in Kuala Lumpur.
He said also that Malaysia welcomed the call for an independent investigation into the disaster.
Al Jazeera's Neave Barker, reporting from Schiphol airport in Amsterdam, said the fear among relatives of the Dutch victims was that crucial time may have been lost shortly after the crash when investigators should have been at the scene.
"The plane crashed in a disputed area, a place where Ukrainian forces and separatists are at bitter loggerheads," he said. "The worry is that the truth about how and why the plane crashed may be lost in the political dispute."