Among them, young adult females and children were clearly under-represented, suggesting that perhaps the attackers had killed the men but abducted the young females. The practice of raptio is surmised to have existed since anthropological antiquity. Opinion in places such as Europe has been divided over the question of whether prostitution should be considered as a free choice or as inherently exploitative of women. In these cases, children are often used to produce child pornography, especially sadistic forms of child pornography where they may be tortured. In areas controlled by Catholic priests , clerical abuse of nuns , including sexual slavery, has been acknowledged by the Pope. Commercial sexual exploitation of children Commercial sexual exploitation of children CSEC includes child prostitution or child sex trafficking , child sex tourism , child pornography , or other forms of transactional sex with children. Child sex tourism Child sex tourism is a form child sex trafficking, and is mainly centered on buying and selling children into sexual slavery. This ruling challenged the widespread acceptance of rape and sexual enslavement of women as an intrinsic part of war. Commercial sexual exploitation is not the only form of human trafficking and estimates vary as to the percentage of human trafficking which is for the purpose of transporting someone into sexual slavery. As such, child pornography is often a visual record of child sexual abuse. India 's federal police said in that they believed around 1. Forced marriage A forced marriage is a marriage where one or both participants are married, without their freely given consent. Reflecting an attitude which prevails in many developing countries, a judge from Honduras said, on condition of anonymity: In Neolithic Europe , excavation of a Linear Pottery culture site at Asparn-Schletz , Austria , unearthed the remains of numerous slain victims. Bride kidnapping has reportedly occurred in countries spanning Central Asia , the Caucasus region , parts of Africa , and among the Hmong in southeast Asia, the Tzeltal in Mexico, and the Romani in Europe. Forced prostitution Most, if not all, forms of forced prostitution may be viewed as a kind of sexual slavery.