TWO beauty contestants have been dramatically detained at a Moscow airport for allegedly seeking to sell an 18-year-old female student as a sex slave, police have said.

The suspects were arrested after allegedly clinching a deal to sell the girl into a world of depraved torture and prostitution with a buyer in a Middle Eastern country for $33,790.

The student was led to believe she had secured a job as a nanny in the unnamed country.

But in reality the teen would have been stripped of her passport, beaten, kidnapped, and forced to work as a prostitute in a brothel, say Russian police sources.

The detained women are beauty contestants Ksenia Starikova, 22, a mother-of-one and the alleged mastermind of the scheme, and Tatiana Petrova, 19.

A video shows them hiding their faces after they were detained by police at Domodedovo Airport in Moscow.

They were held as Ms Petrova prepared to board a plane bound for Turkey with the victim, it was alleged.

It is unclear if this was the final destination.

Police staged a sting operation posing as buyers, and the women were arrested after Ms Starikova received the money at the airport, it is alleged.

Ms Starikova, who is a Mrs Russia 2017 finalist, is divorced from her military husband and is a single mother with a 14-month-old daughter.

Ms Petrova says she is a Russian-Bulgarian model and was a finalist in the Top Russia International 2018 beauty contest.

Both women have been charged with human trafficking and face up to six years in jail if convicted.

The older suspect, reported as running a "modelling agency" while also studying for a master's degree and working as a gymnastics coach, is held in detention.

Ms Petrova is assisting police in explaining their trafficking plan, and is under house arrest, said law enforcement sources.

Police say the women found a buyer for the student - fluent in English and German - on social media.

They negotiated with him for several weeks before agreeing the deal and taking the victim to Domodedovo Airport in Moscow.

The teen victim was described as a student of a foreign languages university in Moscow who had graduated with honours from her school.

The young girl was originally from Serpukhov, 60 miles south of Moscow.

Ms Starikova was detained for two months in detention pending investigations into the case.

This article originally appeared in The Sun and has been republished here with permission