Women in Iran have told the BBC how their online activity has been spied on by the authorities, leading to arrests, threats and beatings.

Iran stepped up surveillance following nationwide women-led anti-establishment protests, after the death in police custody two years ago of 22-year-old Mahsa Amini, who was arrested for allegedly not wearing her hijab properly.

Warning: The following article contains descriptions of violence. Some names have been changed to protect individuals’ identities.

Like many of the women inspired by the protests, Alef posted a photo on social media revealing her hair flowing freely in public. It was a simple act of solidarity with the movement against the forced wearing of the hijab.

“I didn’t really care enough to hide who I am or where the photo was taken,” she said. “I wanted to say, ‘we exist’.”

But the picture was seen by the authorities, which were trying to crush the protests, and Alef was arrested.

She says she was blindfolded, handcuffed and taken to an unknown location where she remained in solitary confinement for nearly two weeks. She was also interrogated multiple times.