Members of a gang who forced Vietnamese girls and women into slavery in nail bars (nail salons) in Britain have been jailed for a total of nine years in what police believe is the first case of its kind.

Giang Huong Tran, 23, Viet Hoang Nguyen, 30, and Thu Huong Nguyen, 49, were sentenced on Tuesday after being convicted of human trafficking and modern slavery offenses.

Police said the "sophisticated money-making operation" involved the exploitation of vulnerable Vietnamese teenagers who were physically and verbally abused.