Twenty-four persons were arrested on Sunday morning after they were found to be living in Malta illegally.
The arrests were made in raids around Hamrun and Qormi.
The arrested persons came from Senegal, Ghana, Nigeria, Gambia, Mali, the Ivory Coast, Benin, Guinea, Niger, Ethiopia and Somalia, the police said.
They are being held at the Detention Centre until arrangements can be made for their expulsion.