Nearly 150 buses will be part of the convoy, which will set off from Istanbul on March 6, making stops at the cities of Izmit, Sakarya, the capital Ankara and Adana before reaching the southern Hatay province along the Turkish-Syrian border.

Gulden Sonmez said the Conscience Convoy has identified 13,581 women by name who have suffered in these prisons since the beginning of the war in 2011.

 "Some of these women lost their lives as a result of torture and rape in prison, while others are waiting to be rescued," she said.

Sonmez said her team had spoken to more than 100 Syrian women who suffered torture in these prisons and are now living as refugees in Turkey.

"They told us what happened to them, what happened to young girls. The Assad regime is using women's bodies as a tool to win this war.

"The world is silent. These women are screaming loudly in these prisons, but no one hears their voices," she said.