Iran has banned women and female journalists from attending World League volleyball matches in Tehran, the IRNA news agency has reported.
Women were reportedly turned away from the Azadi Stadium when Iran played Italy on Friday, while female reporters inside the complex were ordered to leave.
"Female journalists are banned from entering the stadium for the next three matches in Tehran," IRNA reported, without giving details.
National police chief-general Esmail Ahmadi Moghaddam said it was "not yet in the public interest" for men and women to attend such events together.
"We cannot allow the presence of women in stadia. The police are applying the law," he said in comments reported by Fars news agency.
According to the Khabaronline news website, authorities had confronted female journalists holding press credentials issued by Iran's National Volleyball Federation and ordered them out.
Journalist Fatemeh Jamalpour, of the Shargh daily, said a small group of female fans who were protesting outside had been detained by the authorities. Jamalpour was also taken into custody and held for six hours, she said on her Facebook page.
The IRNA did not provide an explanation for the ban, whch has been decried by the Iranian vice- president Shahindokht Molaverdi.
She was reported by media as saying that Iran's President Hassan Rouhani, who advocates more social freedoms in the Islamic republic, was looking at ways to resolve the issue.
Iranian women have only once been allowed to attend the World League since 2013, when the country started playing in the tournament. Since then, however, female journalists had been allowed to cover the games.
Women are also banned from attending football matches in Iran, as according to officials, this protects them from the lewd behaviour of male fans.
Police have prevented the public screening of 2014 World Cup matches from Brazil, despite Iran's participation, forcing fans to watch the games indoors.