mh17 crash site
A pro-Russian separatist stands at the crash site of Malaysia Airlines flight MH17, near the settlement of Grabovo in the Donetsk region, July 18, 2014. reuters/Maxim Zmeyev

Access to the crashed remains of Malaysia Airlines Flight MH17 was blocked by pro-Russia rebels who prevented a team of international investigators from reaching the site, BBC reported Saturday.

Michael Bociurkiw, a member of the Organization for Security and Cooperation -- which arrived at the crash site on Friday -- told BBC that their access had been limited, despite assurances from regional rebel commanders.

"We had expected unfettered access, that's the way we work,” Bociurkiw told a news conference, adding that their job had been made difficult due to the presence of “armed personnel who acted in a very impolite and unprofessional manner.”

He also said that “a visibly intoxicated armed guard” had fired shots in the air when one of the investigators strayed away from the rebel-prescribed area.

The Boeing 777-200, which was on its way from Amsterdam to Kuala Lumpur, was reportedly shot down by a surface-to-air missile over eastern Ukraine on Thursday, killing all 298 people on board. The plane came down near the village of Hrabove, about 25 miles from the Russian border, in the country’s war-torn Donetsk region. The territory is under the control of pro-Russia rebels from the self-proclaimed Donetsk People’s Republic.

Meanwhile, following clashes between Ukrainian forces and rebels in the eastern city of Luhansk, which reportedly left 44 people dead, Ukraine's defense minister said late on Friday that government troops had taken control of the southeastern part of the city.

According to a statement published on the Defense Ministry website late Friday night, Valeriy Heletey, the Ukrainian defense minister, told President Petro Poroshenko that “the Armed Forces of Ukraine took control of the south-eastern part of the city of Lugansk (sic).” It also added that the armed forces had been successful in “unblocking” the Ukrainian military airport in Luhansk.

Several explosions were also heard overnight in the rebel-held city of Donetsk --about 100 miles southwest of Luhansk -- BBC reported Friday.

More than 1,000 civilians and combatants have been killed in eastern Ukraine since mid-April, when government security forces moved to regain control. Thousands of people have fled the ongoing violence in the region since.

The MH17 crash site lies between Krasni Luch in Luhansk region and Shakhtarsk in Donetsk region. There has been no sign of a cease-fire in eastern Ukraine despite pressure for a truce following Thursday's plane crash.