MH17 US Secretary of State John Kerry said on Sunday that the evidence indicates that a Russian missile was used to shoot down Malaysia Airlines flight MH17, reports Reuters .

Moscow denies involvement in shooting down the airliner and has blamed the Ukrainian military.

But Washington and its allies point the finger at the pro-Russian separatists who have Moscow's backing and have been accused of obstructing access to the crash sites.

Kerry said the United States had seen supplies moving into Ukraine from Russia in the last month, including a 150-vehicle convoy of armored personnel carriers, tanks and rocket launchers given to the separatists.

The United States had intercepted conversations about the transfer to separatists of the Russian radar-guided SA11 missile system it blames for the downing of the Boeing 777, he said.

"It's pretty clear that this is a system that was transferred from Russia," Kerry was quoted as saying in an interview on CNN .

Earlier today, Ukraine's counterintelligence claims it has photographic evidence that points to the Russian-backed separatists as the perpetrators of the downing of MH17.

In a briefing at the Ukraine Crisis Media Center, head of Ukraine’s Security Service (SBU) counterintelligence department Vitaliy Nayda claimed photo materials show two BUK-M1 missile systems crossed the border from Ukraine into Russia at 2am (Ukraine time) on July 18 - the day after MH17 was shot down.

"One of them had a full set of four missiles, the other - three missiles," he said.

This apparently was an attempt by separatists to cover their tracks, according to the Ukraine Crisis Media Center in a report on its website last night.

According to Nayda, three Russian BUK-M1 were located on Ukrainian territory controlled by separatists at the time when the plane was downed.

He told reporters they have evidence of a missile being launched at 4.20pm (Ukraine time) on July 17 from an area near Torez at the ill-fated Malaysian passenger aircraft.

He claims one of the systems, operated by a crew of three Russian citizens fired the missile that hit MH17 airliner from a location near the town of Snizhne in the Donetsk region.

Nayda also cited Ukraine’s Security Service intercepting phone conversations that they say confirm at least one BUK-M1 had previously arrived into Ukraine from the Russian Federation, with a crew of three Russian military personnel.

He was reported displaying a photo of a BUK-M1 on the streets of Torez to the media present at the briefing.

Cover up attempt

Nayda also claimed that the separatists had planned to actually hide the bodies once they discovered that they had shot down a passenger plane.

"When militants discovered that they had downed a passenger airliner, they tried to remove the bodies, driving them away from the site on trucks.  

"However due to the large number of bodies, the terrorists abandoned this plan," he was quoted as saying.

Nayda emphasised that Russia is obligated to provide all information to further the investigation.

"We will find all the answers once we arrest the terrorists responsible for this act of terror," he added.

Meanwhile according to Bernama , the Ukrainian government has claimed that the Russian-led terrorists were obstructing the launch of an investigation on the MAS airplane crash in Ukraine on Thursday.  

38 bodies moved, evidence destroyed 

According to the latest posting on the web portal of the Ukrainian government, the Russian-led separatists were preventing access of the international community and foreign governments to the location of the crash.         

"The government was informed that the terrorists moved 38 bodies of the victims to the morgue in Donetsk, where the “experts” with Russian accent claimed that they intend to perform autopsies.       

"The terrorist groups are also seeking to obtain large cargo transport to move the remnants of the aircraft to Russia," the website added.      

The website further said, the Ukrainian government officially states: the "terrorists", with Russia’s support were attempting to destroy the evidence of this international crime. 

"We urge the international community to oblige Russia to withdraw its terrorists from Ukraine and to allow the Ukrainian and international experts to hold a comprehensive investigation on the tragedy," it added.             

The website further said there would be no pardon for the international criminals, nor for those who supported them, who trained them, financed them and supplied weapons to them.   

"The (Ukrainian) government provided all necessary technical equipment and personnel to hold the investigation and forensic examinations, as well as all means to repatriate the victims’ bodies to their respective countries.         

"But at this stage, the Russian-led terrorist groups prevent this from happening," the website said.    

'Working at gunpoint'

The MAS flight, MH17, was flying from Amsterdam to Kuala Lumpur when it went down in Donetsk, eastern Ukraine near the Russian border on Thursday night.   

The Boeing 777-200 aircraft was carrying 298 people - 283 passengers and 15 crew.    

The Ukraine authorities claimed that the aircraft was shot down.    

There is also a claim that 170 Ukrainian experts were working gun pointed at MH17 crash site in the Donetsk region, according to Ukraine Crisis Media Centre website , a website launched by the Ukrainian government to provide international community objective information about events in the country.       

During a briefing at the center in Kiev, a spokesman for the Ukrainian Security and Defense Council Information Centre, Andriy Lysenko said search and rescue operation was ongoing at the crash site of MH17 in Sharkhtarsk district of the Donetsk region.             

Lysenko emphasized that the search operation was complicated because of the presence of armed terrorists in the area.       

"They continue to impede the work of the Ukrainian rescue personnel keeping them under the barrel of a gun," he added.            

Lysenko added the search operation covers an area of 25 sq km and an area of about 18 sq km has already been searched, and a team of divers has searched more than 2 sq km of the water reservoir.    

"As at 07:00am on 19 July (Ukrainian time), 186 bodies had been found," he said adding that the search operation involved 100 experts of the State Emergency Service of Ukraine and 18 items of equipment, together with 70 Interior Ministry experts.