Estimates of abductions during the war range from 14,000 to 200,000. One estimate (by Jok Madut Jok) is of 10–15,000 slaves in Sudan "at any one time", the number remaining roughly constant as individual slaves come and go—as captives escape, have their freedom bought or are released as unfit for labor, more are captured. Until 1999, the number of slaves kept by slave taker retains after the distribution of the human war booty was usually "three to six and rarely exceeded ten per slave raider". Although modern slave trading never approached the scale of nineteenth-century Nilotic slavery, some Baggara "operated as brokers to convert the war captives into slaves", selling slaves "at scattered points throughout Western Sudan", and "as far north as Kharoum". Illegal and highly unpopular internationally, the trade is done "discreetly", and kept to a "minimal level" so that "evidence for it is very difficult to obtain." "Slave owners simply deny that Southern children working for them are slaves."