KIEV, Ukraine – Evidence from the black box of Malaysia Airlines Flight 17 indicates that shrapnel from an exploding missile ripped through the passenger jet, causing a "massive explosive decompression" that led to the crash and death of 298 passengers and crew, a Ukrainian government official said Monday.

Col. Andriy Lysenko, the spokesman for the Ukrainian Security and Defense Council, said he was repeating information from the investigation commission that is studying the black box from the Boeing 777 passenger jet. If true, it would be the first solid evidence of what downed the aircraft. The commission itself has not commented on its findings. "This is real information, from the investigation," Lysenko said. "We're not making this up."

Despite the widespread assertion that a surface-to-air missile downed the aircraft, there has been virtually nothing collected from the crash site that would help investigators piece together the sequence of events that led to Flight 17's plunge to earth.

Lysenko said that ground investigators once again were unable Monday to work inside the 25-mile diameter area thought to contain the jet's wreckage, the condition of which would provide important clues to what precisely happened.

Fighting hinders work

At a news conference in Kiev, Australian Foreign Affairs Minister Julie Bishop said a team of Australian and Dutch investigators was on the ground and ready to carry out the investigation.

Flight 17's passengers and crew came from 11 nations, with the vast majority from the Netherlands. There were 27 from Australia.

in kiev: Despite fighting in eastern Ukraine, Ukrainian Orthodox Church Kiev Patriarchate Filaret conducted a service to celebrate the 1026th anniversary of the region’s conversion to Christianity. Afterward, thousands marched, some carrying icons and the national flag of Ukraine.

Bishop made it clear that the combined investigation team had no interest in getting involved in the deadly conflict in eastern Ukraine between pro-Russian separatists and Ukrainian security forces.

"We are here for one purpose, and this is to ensure that the site is secured, to enable us each day to scour it for remains for those aboard MH17, and to commence the crash site investigation," she said.

Lysenko said that the effort was again thwarted by fighting in the region. Lysenko said that Ukrainian security forces have not engaged in fighting inside the crash area. But he alleged that pro-Russia separatists are thought to have been shooting inside the area in an attempt to destroy evidence.