Portuguese authorities said on Monday (20 January) they had started looking into media leaks concerning Angolan billionaire Isabel dos Santos, while a small bank said it had decided to put an end to commercial relationship with entities controlled by dos Santos.

Portugal’s central bank said in a statement it had asked Eurobic bank about transfers between Angola and Dubai while a spokesman for Portugal’s prosecutor office said it would investigate reports about dos Santos, in the latest fallout from increased scrutiny of Angola’s former first daughter.

The central bank statement, the prosecutor’s office and Eurobic all referred to hundreds of thousands of files dubbed the “Luanda Leaks” – obtained by the International Consortium of Investigative Journalists (ICIJ) and released by several news organisations on Sunday.

The documents that form the basis of Luanda Leaks came to the International Consortium of Investigative Journalists from Paris-based Platform to Protect Whistleblowers in Africa.

The files reveal how Isabel dos Santos, the richest woman in Africa and daughter of long-serving African strongman president, José Eduardo dos Santos, moved public money out of one of the poorest countries on the planet into tax havens and beyond.

The leak is comprised of more than 715,000 documents, including emails, contracts, spreadsheets, audits, incorporation papers, organizational charts, board of directors meeting minutes and videos, loan agreements, deeds, public contracts, invoices, tax advice and tax returns.

ICIJ publishes documents in the public interest that complement our rigorous and fair reporting. For security, privacy and ethical reasons, ICIJ does not publish documents en masse.

Dos Santos, who holds a 42.5% stake in Eurobic indirectly via two entities and does not sit on the board, had said on Sunday that allegations made against her were “completely unfounded”.

Eurobic did not say what its decision to sever ties with entities linked to dos Santos would mean for its own relation with its main shareholder, who is dos Santos.