LISBON (Reuters) - Angolan billionaire Isabel dos Santos said on Monday she was launching legal action against a consortium of journalists and its media partners over the publication of thousands of documents about her business empire.

FILE PHOTO: Isabel Dos Santos, daughter of Angola’s former President and Africa's richest woman, sits for a portrait during a Reuters interview in London, Britain, January 9, 2020. REUTERS/Toby Melville/File Photo

Dos Santos, whose father Jose Eduardo dos Santos was Angola’s president for 38 years until 2017, said the documents released last week by the International Consortium of Investigative Journalists (ICIJ) and its media partners were part of a “concerted and intense campaign” against her.

“I refute the unfounded allegations and false affirmations and inform that I have taken steps towards initiating legal action against ICIJ and its partners, which will be managed by the international law firm Schillings Partners,” dos Santos said in a statement.

The ICIJ was not immediately available for comment.

Angola has named dos Santos as a suspect over alleged mismanagement and misappropriation of funds while she was chairwoman of state oil firm Sonangol in 2016-2017.

She has denied the allegations, and focused Monday’s statement almost exclusively on the contents of documents revealed in the so-called Luanda Leaks regarding payments made by Sonangol under her chairmanship.

Dos Santos hired Matter Business Solutions to coordinate the services of the various consultancies involved in the restructuring of Sonangol, including Boston Consulting Group, PwC, and McKinsey.

Monday’s statement said Sonangol spent $90 million on Matter’s services over 18 months, which she says is less than the $12 million per month spent in 2014-15 under her predecessor.

Sonangol was not immediately available to comment.

The three consulting firms stated last week they were cutting ties with dos Santos’ businesses.

Dos Santos’ latest statement makes no reference to a further transfer of $38 million from Sonangol to Matter just a few hours after her dismissal from Sonangol’s board by current president Joao Lourenco.

Dos Santos said the Luanda Leaks were based on “emails obtained criminally via hacking to create a misleading narrative”.

A Portuguese hacker, Rui Pinto, has taken responsibility for disclosing hundreds of thousands of files “containing all data related to the recent revelations” about dos Santos’ fortune” to an African whistleblower platform, his lawyers said on Monday.

Dos Santos says the leaks were part of a politically motivated campaign by the government of her father’s successor.