Three members of the radical feminist group Femen have been arrested after staging a topless protest in front of Tunis's central courthouse in support of Amina Tyler, the Tunisian activist arrested earlier this month.
The women, two French and a German, shouted "free amina" before being held by authorities, according to AFP.
Amina, 19, is in custody and will face trial on 30 May for being in possession of pepper spray.
She was arrested in the central city of Kairouan as she protested against Salafist movement Ansar al-Sharia, which is planning to hold a congress in defiance of a government ban.
Videos posted online showed Tyler painting the word "Femen" on a wall near the Karouan mosque.
Interior ministry spokesman Mohamed Ali Aroui described her gesture as "immoral."
Before her arrest, Tyler went missing in April for the second time after receiving death threats for posing topless with the words "f**k your morals" emblazoned across her chest, echoing protests staged by Femen.
Her topless picture triggered a furious reaction from politician Adel Almi, a radical Muslim and extremist imam who heads the Commission for the Promotion of Virtue and Prevention of Vice. He subsequently decreed she deserved to be whipped or even stoned to death.
Femen staged a number of bare-breasted protests across Europe as part of a Topless jihad day in her support. The initiative was criticised by a group of Muslim women who launched a counter protest against Femen. Amina herself appeared on video to distance herself from the protests but later said she had been forced to do so.