The health of a 16-year-old Iranian girl who has been in a coma since an alleged assault on the Tehran metro has "deteriorated" in the hospital, local media reported Wednesday.
According to the state news agency IRNA, Armita Garawand fainted because of low blood pressure.
But a Kurdish-focused rights group has alleged that she was hurt in a clash with female police officers on the network, for allegedly violating Iran's strict dress code for women.
"Despite the continued efforts of the medical staff at Fajr Hospital, Armita Garawand's relatively stable vital signs have changed and deteriorated... over the past few days," said Borna news agency, which is affiliated with the sports ministry.
"However, the medical team's efforts to improve Armita Garawand's condition continue," it added.
Garawand lives in Tehran but hails from the city of Kermanshah, some 500 kilometres (310 miles) from the Iranian capital, in Kurdish-populated western Iran.
Western countries, including Germany and the United States, and rights groups have raised concerns about the case after a purported video of the incident circulated on social media.
In September last year, the death of another Kurdish-Iranian woman, Mahsa Amini, for allegedly breaching the Islamic Republic's strict dress code for women sparked wide-ranging protests.
Amini was arrested near a Tehran subway station.
Armita, who was with friends and apparently not wearing a headscarf, is said to have been pushed into the metro train by female police agents.
Last week, Iran's foreign ministry spokesman, Nasser Kanani, criticised Western comments on the case as "interventionist".
The head of the Tehran subway system has also denied there was any verbal or physical altercation between the teenager and passengers or staff.
IRNA later published interviews with two girls who said they were Garawand's friends who confirmed the account.