"An investigation to establish the cause and circumstances of the aircraft crash is being carried out," the department's spokeswoman Tatyana Dubinyuk said. "We are not giving out any information on the criminal case in the interests of the investigation," she said.
Last Friday's Mi-171 crash killed seven people, including the Russian president's envoy to the State Duma, Alexander Kosopkin and a regional environmental official, Viktor Kaymin, who were part of a hunting trip to the mountainous area. Four people survived the crash.
Dubinyuk said specialists were continuing work at the crash site. However, on Wednesday she said the investigation had been completed.
The government of the Republic of Altai earlier confirmed the helicopter passengers were hunting animals and had licenses to hunt goats and deer, amid reports that the party had killed an endangered species of mountain sheep.
In a photograph from the crash site, posted on an Altai Internet site, the carcasses of Altai mountain sheep, or argali, are clearly visible among the helicopter wreckage. There are reported to be just 200 Altai mountain sheep remaining in Russia.
According to some reports, the crash may have been caused when the helicopter captain descended to a minimum altitude either to pick up the carcass of a shot mountain goat, or to take a better aim.
WWF Russia issued a statement confirming that the slain animals were mountain sheep and demanded an investigation into the incident.
A spokesman for the Russian nature resources ministry, Nikolai Gudkov, said hunting rare animals is allowed only in "exceptional cases" such as preserving the population and preventing the spread of disease. It requires a special license from the environmental ministry and is applied mainly to polar bears.
The Mi-171 is an export version of the Mi-8 Hip helicopter, which is currently in production at two factories in Kazan and Ulan-Ude. According to the investigation, the crashed helicopter was in good working order and flying on high quality fuel.