Beijing — A cruise ship disaster in central China this year that killed all but a dozen of the hundreds of people onboard was caused by violent weather, according to the findings of a government investigation released Wednesday.

The inquiry into the June 1 disaster on the Yangtze River also found that the captain of the ship and dozens of officials had contributed to the tragedy through poor decisions and laxity.

The ship, the Oriental Star, capsized and sank after heavy rains and ferocious winds battered it as it was sailing at night near Jianli County, in Hubei province. Of the 454 people onboard, 442 died, and the accident became one of several in China in 2015 that ignited accusations that lax regulations, bungled decisions by officials and even corruption created the conditions for such calamities.

But the investigation, overseen by the Chinese central government, concluded that the disaster was primarily due to extraordinarily destructive weather, according to the report issued on the website of the State Administration of Work Safety.

“The sinking of the Oriental Star arose from sudden and rarely seen severe convective weather (a squall line accompanied by a downburst) that brought an onslaught of strong winds and heavy rains that led to this extraordinarily grave disaster,” the report said.

“The capacity of the Oriental Star to withstand winds and resist overturning was in line with the regulatory requirements, but it was not enough to withstand the extremely bad weather that it encountered,” the report said.

The accident occurred while the Oriental Star was on a pleasure cruise, ferrying passengers, many elderly, on a multiday trip to Chongqing from Nanjing. The captain struggled to keep the ship steady as the winds lashed and twisted it, according to the summary of the report, but the storm’s force was about twice what the ship could handle.

The inquiry found no grounds for speculation that the ship had been rushing to arrive at a meeting place before the departure of a bus; the Oriental Star had slowed down, the report said.

The report went to great lengths to describe the efforts taken by investigators from six ministries and agencies, as well as other branches of government, to reach their findings, apparently anticipating skepticism from citizens who often believe that negligence is behind such deadly accidents.

In an effort to bolster the credibility of the findings, the official news agency Xinhua also released a question-and-answer explanation from four experts who took part in the investigation. The experts dismissed reports, which circulated shortly after the disaster, that a tornado had also struck the Oriental Star.

“The captain did not abandon his ship before the incident,” said one of the experts, Song Jiahui. “There was no problem of the ship rushing to make time.”

Concern about public safety in China has been magnified by other recent disasters, such as explosions at a toxic chemical storage site in Tianjin in August that killed at least 173 people, and the collapse at a dumpsite in Shenzhen on Dec. 20 that left dozens missing and presumed dead. In both of those cases, officials acknowledged that human error and missteps were to blame.

The captain of the Oriental Star, Zhang Shunwen, and its chief engineer were among the 12 survivors, and the police detained them soon after the sinking.

“The captain and first mate on duty had insufficient knowledge of extreme weather and its risks,” the report said. “They never issued a distress message, did not issue a warning to the whole ship, and did not organize steps to abandon ship and disperse passengers.”

The inquiry said Zhang should be stripped of his captain’s license and investigated for possible crimes. The first mate, with whom it also found fault, died in the sinking.

The investigators also recommended administrative penalties against seven managers of the Chongqing Oriental Ship Co., which operated the Oriental Star, and 36 government and Communist Party officials deemed to have fallen short in supervision and inspections. They also recommended firmer restrictions on passenger ships sailing on the Yangtze River in poor weather.