Rubbing the lines of dirt in his thickly-callused hands, Kurban Kalambarov says he is a "slave" at the Mytishchinsky construction goods yard in northern Moscow where he works as a cleaner.
"My children will be slaves too," says Kalambarov, 40, who like many thousands came to Moscow from the Central Asian state of Tajikistan last year to earn money for his family back home.
"The higher-ups in government understand that you need more immigration, but the police sergeants just say: Youre niggers, get out of here'."
President Vladimir Putin has called for more immigrants like Kalambarov to come to Russia to make up for labour shortages created by a growing economy and a rapidly shrinking population. But the conditions they face are often grim.
Identity papers are held by employers, wages are not paid, registration papers are ripped up by police officers to extort bribes, several immigrant workers too afraid to be named told AFP in Moscow.
"There are problems as soon as you step out of the market. The police can shake you down," says Amir, 44, a grey-haired porter at the Cherkizovsky market.
A report last month by UNICEF found that around one million immigrants in Russia constitute "an at-risk group whose situation is more or less close to slavery."
Thousands of immigrants in Moscow live in metal containers on the many building sites and markets where they work. They do not speak out for fear of losing both their jobs and their housing.
The trouble is also that "immigrants are ready to work under these conditions" out of financial desperation, says Boris Soshenko, head of the Russian Builders Union.
The union is unique in having more than 3,000 members who are unregistered immigrants and tries to force the heavyweight companies behind Moscows construction boom to pay them wages.
Trade union officials say "many" die nameless deaths on the building sites or break their backs in falls. No-one knows exactly how many, because no-one is counting.
Referred to as "churki" by many Russians -- a word literally translated as "logs" but intended to mean "idiots" -- immigrants from poor former Soviet Central Asia can become easy prey for corrupt police officers.
One police source working in an immigrant-heavy Moscow neighbourhood told AFP that once or twice a week officers plant false evidence on migrant workers to extort bribes.
"People without registration, without contracts are very vulnerable," says Anna Ruptsova, a researcher at the Moscow office of the International Organisation for Migration.
Ruptsova says 500,000 immigrants flock to Russia every year legally, coming mainly to large population centres such as Moscow to work as porters, builders and cleaners.
But around three million -- the biggest share from Tajikistan -- come without registering and often for only several months at a time to send money to their families back home, she adds.
Tajik nationals dont need visas to travel to Russia, but must register at their place of residence within three days of arrival.
Many cant because they live in places not considered habitable by the law. Virtually overnight, the new arrivals become illegal.
The Russian parliament last month approved the first draft of a law intended to ease registration rules.
But without decent housing provision -- "its not going to have much effect," Ruptsova explains.
Russian officials have long discussed a possible "amnesty" that would give official registration and work permits to some or all of the immigrants currently in Russia.
But the idea is politically unpopular because of strong grassroots opposition to the presence of immigrants among the many locals who hate the colour of their skin.
Last November, a rally by the Movement Against Illegal Immigration brought 1,000 people into the streets of Moscow and in December a major political party, "Motherland," campaigned on an openly racist platform for Moscow local elections.
Raisa Safaraliyeva, 54, has lived in a room with three other Tajik women in a flat in northeast Moscow since stepping off the train from Tajikistan four months ago.
Her lack of official registration means she is having trouble finding a job.
"Were not allowed to work here, were not allowed to do anything. What are we going to do -- be bums?" says the former primary school teacher.
Selling chewing tobacco at a rickety cafe in an old railway carriage at the construction yard, she remembers the warm welcome she received last time she came to Moscow in her youth.
Now, she is greeted with daily racist abuse. "They call me animal when I ride on the train... They say Im dirty," she says, pointing to her spotless flower print dress and white cardigan.