A four-year-old girl who walked miles through the freezing Siberian wilderness to get help for her sick grandmother has been hailed as a hero in Russia's Tuva republic, while a criminal case has been opened against her mother.

Saglana Salchak had been living with her grandparents at their remote farm deep in the taiga forest near the Mongolian border, more than 12 miles from the nearest village and five miles from their closest neighbour.

Last month the child awoke to find that her 60-year-old grandmother was not moving. After talking with her blind grandfather, she decided to walk to the next homestead for help, according to local news.

Taking only a box of matches in case she had to light a fire, the four-year-old set out into the early-morning darkness, where temperatures hit -34C (-29F). It took her several hours to walk the five miles along a river bank through snowdrifts. Fortunately, she did not get stuck in the snow, often chest high, or encounter any of the wolves that had at times attacked her grandparents' livestock.

"Tuva has simply filled up with wolves," Semyon Rubtsov, head of the regional search and rescue group, told the Komsomolskaya Pravda newspaper. "They eat the livestock - the herders moan about them. She could have easily stumbled on a pack in the darkness."

After five gruelling miles Saglana nearly missed her neighbours' house amid the undergrowth, and would have passed it if one of them had not spotted her. They called in medical personnel from the village, who, after checking on the girl, made the trek back to her grandparents' place. There they discovered that the grandmother had died of a heart attack.

Saglana told Komsomolskaya Pravda she was not scared making the trip through the forest alone. "I just walked, walked and got there," she said. She admitted, however, that she had been cold and had "really wanted to eat".

Although she caught a cold, Saglana quickly recovered at the local hospital and is now living at a social centre, where she just celebrated her fifth birthday. Local media have declared her a hero. "You can't [easily] impress residents of the remote Tere-Kholsky district with extreme stories about taiga life. Nonetheless, the incident several days ago amazed even the old-timers in Kungurtug, the district centre," Tuva Online also wrote about Saglana's feat.

Saglana's mother and stepfather look after their own herd of horses in another part of the region. The social policy ministry offered the youngster a free trip to a sanatorium with her mother, Eleonora, when she returns from herding in May.

But on Sunday, the Tuva investigative committee opened a criminal case against Eleonora Salchak for leaving a minor in danger. "She knew that the elderly [grandparents] lacked the ability to take measures to guarantee the child's safety," it said in a press release. If charged, the mother could face up to a year in prison. The committee said it was also investigating the actions of social policy officials in the girl's district.

Sayana Mongush, an activist and journalist in the regional capital of Kyzyl, told the Guardian that it was shocking Salchak's grandparents didn't have any phone or internet connection, especially since defence minister and Tuva native Sergei Shoigu previously promoted archeological digs at an ancient fortress located in their district.

"Even in Soviet times, herders in Tuva had [material] privileges and radio communications," she said. "But now in the 21st century a four-year-old child has to go by foot only because there's no connectivity. This is nonsense, and the crime is not by the girl's mother, but by the authorities."

A sparsely populated republic of rugged forests, mountains and plains, Tuva is renowned for its traditional throat-singing and for ancient shamanistic religious practices, which coexist alongside Buddhism.