Three people have been charged with immigration offences and another man is being deported to Nigeria after an inquiry into suspected sham weddings.
The case involved simultaneous arrests across England and Holland.
The investigation started when several Nigerians applied to settle in the UK after getting married in Nottingham.
Officials were suspicious because they used the same church and all married Dutch nationals, who are entitled to live in the UK.
Immigration officials are still waiting to question a man arrested by Dutch police who is due to be extradited from Holland.
Two men and one woman have been charged with conspiracy to commit an offence under Section 25 of the Immigration Act - assisting unlawful immigration - and they have been remanded until 9 June.
One man was arrested at the University of Nottingham and one woman at another address in Nottingham, while a second man was arrested in Ramsgate in Kent.