At least four more people have been taken under custody for wearing controversial “hero” T-shirts over the past two days, according to Turkish media.

The hero T-shirts became a contentious issue when Gökhan Güçlü, one of the suspects on trial for an assassination attempt against President Recep Tayyip Erdoğan on the night of the coup, was thrown out of the courtroom last week for wearing a T-shirt bearing the word “hero” because it caused tension between the parties during the hearing.

At least 30 people have been detained for wearing hero T-shirts since then.

In Adana, police rounded up Şahin B. after he took a university transfer exam with a hero T-shirt on him on Sunday. Meanwhile, Adana police also detained 17-year-old S.E.G. in Yesilyurt Street the same day.

28-year-old Murat Y. was detained in Trabzon’s Salpazarı district on Monday and 25-year-old M.B. was taken into custody in Sivas’s Susehri district.

President Recep Tayyip Erdogan said people detained over coup charges should wear a single outfit, like in Guantanamo.

In the meantime, the textile firm that manufactures the hero T-shirts stopped production and the T-shirts were withdrawn from sale in stores and online.