Human rights lawyer Giti Pourfazel, one of 14 women who had signed a public letter calling on the Islamic Republic’s Supreme Leader Ayatollah Ali Khamenei to step down, has been arrested.

In the letter published August 5, the 14 activists, who all reside in Iran, had called for a transition towards a secular democracy in Iran as a way to remove the “gender apartheid” and “patriarchal approach” that is practiced in the Islamic Republic.

In interviews with media outside Iran, Pourfazel condemned the systemic discrimination against women, which includes compulsory hijab and a ban on women to attend football matches. The issue has again become hot in the country after the international football association FIFA has reportedly given a deadline to Iran to stop the practice and allow women unfettered access to stadiums.

“Four decades of this theocracy has eliminated the rights of half of the country’s population,” the women’s rights activists said in the letter, calling for “civil and non-violent measures” to leave behind “this anti-women system,” and create a new constitution for Iran.

So far, six of the 14 women activists have been arrested. These include: Shahla Entesari, Shahla Jahanbin, Nargess Mansouri, Farangis Mazloum, Guiti Pourfazel and Fatemeh Sepehri.

In July, 14 activists published the initial an open letter calling for an end to the Islamic Republic and for Khamenei to step down. A number of signatories of the first letter have also been arrested.