KATHMANDU (Thomson Reuters Foundation) - A 15-year-old girl in western Nepal suffocated to death after being forced to stay in a poorly ventilated shed because she was menstruating in an age-old Hindu practice banned over a decade ago, police said on Tuesday.

Roshani Tiruwa’s body was discovered by her father early on Sunday in mud-and-stone hut in Gajra village in Achham district, 440 km (275 miles) west of Kathmandu.

“While we are waiting for the post-mortem report for the cause of her death, we believe she died due to suffocation,” Police Inspector Badri Prasad Dhakal told the Thomson Reuters Foundation by phone from Sanfebagar, the main town in the area.

“She had lit a fire to keep herself warm before going to bed in the shed which had no ventilation,” he added.

The girl is the second to die in the region this month due to “Chhaupadi system” - a practice where Hindus banish menstruating girls and women to animal sheds for the duration of their period as they are thought to be impure.

It was outlawed in 2005, but sporadic reports of women and girls dying in attacks by wild animals and from snake bites, or being raped while they are in seclusion in these sheds, indicate the archaic practice still continues in Nepal’s remote west.

Some communities believe they will suffer misfortune such as a natural disaster if women and girls are not sent into isolation when they menstruate. They are also not permitted to drink milk and are given less food to eat during their period.

Activists say the government’s response to stamp out practices such as the Chhaupadi system and child marriage in the Himalayan nation has been inadequate. But officials say they are battling age-old attitudes which cannot be changed overnight.

“We have launched different schemes but quickly removing practices that are deep-rooted in the society is difficult,” said Binita Bhattarai, an official from Women and Child Welfare ministry.

“Changing mindsets and social attitudes is a time-taking process.”