Arif Naqvi, the founder of the collapsed The Abraaj Group, was released from custody May 28 after he paid £15 million for the conditional bail, Bloomberg News reported, citing the founder's spokesman.

Judge Michael Supperstone, who approved the bail in May, said that the bail conditions "effectively amount to house arrest," since Naqvi is required to surrender his travel documents, wear an electronic tag and remain in his London home during the bail, according to the report.

Naqvi is one of several officials of the insolvent private equity firm in the middle of a U.S. fraud probe.