Ahmed Abdallah Mohamed Sambi was questioned by investigators on May 15 over his role in the scheme. He was put under house arrest to stop him from inciting his supporters, the interior ministry said.

In a statement on Sunday, Sambi, who is being investigated along with successor Ikililou Dhoinine and 10 officials from both administrations, accused the government of posting soldiers at his gate to restrict freedom.

Sambi, who has denied all the allegations against him, said the actions risked putting off the country’s partners and shaking the faith of foreign investors in the Indian Ocean archipelago nation.

The Comoros launched a program with the United Arab Emirates and Kuwait in 2008 to sell citizenship to stateless people in those countries, known as Bidoon, in return for cash to help develop the country.

However, an investigation by parliament released earlier this year found that thousands of passports were sold outside official channels via “mafia” networks and at least US$100 million (RM400 million) of revenue went missing.

President Azali Assoumani has said the scheme has since been suspended and promised to hold to account those who broke the law or embezzled money.