The Dyatlov Pass incident

Nine experienced ski hikers lost their lives in the northern Ural Mountains in early February 1959. In 2020 a Russian prosecutor announced that an avalanche caused the deaths, though Kommersant reported that his statements had not been agreed with the Prosecutor General's Office.

In February 1959 nine experienced hikers died on a hard expedition through the northern Urals, as Gaume and Puzrin summarise the case. Wikipedia dates the deaths to 1 or 2 February, in the Russian SFSR. It says the hikers, a Ural Polytechnical Institute group led by Igor Dyatlov, had pitched camp on Kholat Syakhl's eastern slopes. Russian reports call the hikers the Dyatlov group, and the place Dyatlov Pass. Writing for BBC News in 2019, Lucy Ash said the case had drawn a flood of conspiracy theories in the sixty years since, and that in February 2019 Russian authorities surprised many by reopening it.

On 11 July 2020 RIA Novosti reported that prosecutors had found an avalanche to be the cause. Wikipedia sums up the finding: an avalanche most likely drove the hikers out of their camp in a hurry, in poor visibility and without enough clothing, and they died of hypothermia.

Kommersant then reported that Andrey Kuryakov, who had run the review as deputy head of the Prosecutor General's department for the Urals Federal District, had been dismissed. According to the paper, Prosecutor General Igor Krasnov had formally warned Kuryakov after a press conference at which he declared the review finished. Kommersant said it later emerged that his statements had not been agreed with the Prosecutor General's Office, and that he made them for personal reasons, to prepare a dissertation.

In 2021 Gaume and Puzrin returned to the avalanche idea in the journal Communications Earth & Environment. They noted that earlier work had found it a poor fit with the evidence: the slope was gentler than usual, few avalanche signs were found, no trigger was clear, and the victims had unusual injuries. Their model has wind heaping snow uphill of the tent until a slab of it broke away.