The Dutch Safety Board on Tuesday released its preliminary report on the downing of Malaysia Airlines Flight 17, saying the Boeing 777 broke up in the air as a result of structural damage caused by “a large number of high-energy objects” that penetrated it.

There were no indications that the July 17 crash over war-torn eastern Ukraine was caused by a technical fault or by any actions of the crew, the report said.

The 34-page report set out what Dutch aviation investigators think happened, but it did not apportion blame. Ukraine and the West accuse pro-Russian separatists, aided by Russia with troops and firepower, of downing the passenger jet, an event that shocked the world. Russia blames Ukraine and denies supplying separatists in eastern Ukraine.

The plane was airworthy when it departed Amsterdam en route to Kuala Lumpur, Malaysia, manned by a qualified and experienced crew, the report said. The Dutch board, entrusted by the Ukrainians to investigate the crash, said it expected the final report to be published within a year of the crash.

“The cockpit voice recorder, the flight data recorder and data from air traffic control all suggest that flight MH17 proceeded as normal . . . after which it ended abruptly,” a summary of the report said. It said the communications among crew members “revealed no signs of any technical faults or an emergency situation.”

A miniature Malaysia Airlines plane with a text reading “RIP MH17” is displayed Tuesday at Schiphol Airport in Amsterdam at a memorial site for the victims of the Flight 17 air disaster. (Peter Dejong/AP)

Because of the situation in eastern Ukraine, Dutch investigators were not able to freely access the site, so they used satellite imagery, radar and information from the plane’s “black box” recorders to compile the report.

The pattern of damage to the aircraft’s fuselage and cockpit is “consistent with that which may be expected from a large number of high-energy objects that penetrated the aircraft from outside,” the summary said. “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.”

U.S. and Ukrainian officials have said that the plane was shot down by a surface-to-air missile system supplied by Russia and fired from rebel-held territory in eastern Ukraine. The Ukrainian security service released intercepted phone conversations among rebel leaders suggesting that their forces were responsible and that they initially thought they had shot down a Ukrainian military plane, but the authenticity of the recordings was impossible to confirm.

The Dutch report did not mention a missile, but military analysts said the damage to the plane as described in the report was consistent with the impact from a missile designed to explode near an aircraft and destroy it with shrapnel.

The Malaysian government plans to send 20 investigators to the crash site as soon as possible, according to the Ukrainian cabinet’s press office. Deputy Prime Minister Volodymyr Hroysman, who is coordinating Ukraine’s investigation of the catastrophe, told journalists in Kiev that Ukraine is ready to organize a new investigative visit to the site, which has been on the front lines for weeks and largely inaccessible to international teams.

But amid reports of fighting Tuesday morning around the Donetsk airport, neither the Dutch nor the Malaysian government appeared willing Tuesday to immediately send investigators back to the crash site.

All 298 people aboard Flight 17 died when the jet was blown out of the sky over the town of Hrabove, about 48 miles east of the rebel-held city of Donetsk. The victims included 43 Malaysians and 195 Dutch nationals, as well as people from Australia, Indonesia, Britain, Germany, Belgium, the Philippines, Canada and New Zealand.

The downing of the jet hardened attitudes against Russia in the five-month-long Ukraine conflict, which the United Nations estimates has killed about 2,600 people.

Violence in eastern Ukraine has significantly quieted as a result of a fragile cease-fire in place since Friday.

Ukrainian military spokesman Andriy Lysenko said at a briefing in Kiev on Tuesday that “this is the first relatively calm day in the east,” although he accused rebels of reinforcing military positions about 20 miles northwest of the city of Luhansk. Rebels said the Ukrainian military appeared to be sending in reinforcements to the nearby town of Shchastya, and each side feared the other would attack.

In a statement on the Dutch report, Malaysian Prime Minister Najib Razak urged “all parties to work closely together to facilitate this investigation and the production of the final report.”

He said the preliminary report “leads to the strong suspicion that a surface-to-air missile brought MH17 down, but further investigative work is needed before we can be certain.”

Michael Birnbaum in Moscow contributed to this report.