Malaysia Airlines Flight MH17 broke apart above eastern Ukraine on July 17 as the result of structural damage caused by penetration of the Boeing 777-200 by a “large number of high-energy objects,” according to a preliminary Dutch Safety Board report issued Tuesday. Furthermore, the board found no evidence of a technical fault or that any crew action caused the crash.

While the U.S. and Ukraine have accused pro-Russian separatists of shooting down the airplane with a missile, the report does not render any conclusions about who, in fact, might have fired it. However, the report supports the theory that a warhead exploded in the vicinity of the airplane. 

The cockpit voice recorder, the flight data recorder and data from air traffic control all suggest that flight MH17 proceeded as normal until 1:20 p.m. UTC, said the report. It added that “a full listening” of the communications among the crew members in the cockpit recorded on the cockpit voice recorder revealed no signs of an emergency. The flight data recorder registered no aircraft system warnings and recorded aircraft engine parameters consistent with normal operation. Radio communications with Ukrainian air traffic control confirm that the crew made no emergency call. The final calls by Ukrainian air traffic control made between 1:20:00 and 1:22:02 UTC went unanswered.

According to the report, the pattern of wreckage on the ground suggests that the aircraft split into pieces during flight. Although the unstable situation in eastern Ukraine has prevented Dutch investigators from examine the wreckage, available images show parts of airplane pierced in numerous places. “The pattern of damage to the aircraft fuselage and the cockpit is consistent with that which may be expected from a large number of high-energy objects that penetrated the aircraft from outside,” said the board. “It’s likely that this damage resulted in a loss of structural integrity of the aircraft, leading to an in-flight break up. This also explains the abrupt end to the data registration on the recorders, the simultaneous loss of contact with air traffic control and the aircraft's disappearance from radar.”