During the protest, police forces reportedly targeted several young men and women participating in the demonstration in order to arrest them. Chaima was present when police officers were arresting one of the activists. As she attempted to pull him away and demanded his release, a police officer sprayed her with a paralyzing gas .

The spray caused her to suffocate and struggle to breathe, in addition to severe burning skin inflammation that remained on her body for several hours. According to her testimony, the gas also caused eye inflammation that prevented her from seeing clearly for hours, forcing her to seek medical treatment at a hospital. There, doctors informed her that such irritant gases can cause serious eye damage upon contact and may lead to significant vision problems.