Former Angolan president Jose Eduardo dos Santos’s son allegedly planned to steal $1.5 billion when he ran the country’s sovereign wealth fund, the finance ministry said.

Jose Filomeno dos Santos (nicknamed “Zenu”) has been accused of “fraud, misappropriation of funds, money laundering and associating with criminals.”

The $1.5 billion figure is three times the sum he was initially accused of illegally transferring to a British bank.

The Angolan finance ministry said that Filomeno dos Santos disguised the transfer as a project aimed at attracting investment to the oil-rich country with the help of a fake guarantee from Credit Suisse.

AFP reported the Swiss back to have said “documents had been forged” and that it had not received “any money relating to this case.”

The finance ministry said $500 million had been transferred to a London bank and that Angola was supposed to make two more such payments.

The first transfer was blocked by UK authorities who suspected foul play.

Filomeno dos Santos – appointed to head the $5bn oil-fuelled sovereign fund by his father in 2013 – was sacked by incumbent president Joao Lourenco in January this year.

Former central bank governor Valter Filipe da Silva, who has been charged alongside Filomeno dos Santos, has promised to “cooperate” with the authorities.

Filomeno’s half-sister, Isabel dos Santos, was also sacked from her job as head of state oil giant Sonangol. Thought to be Africa’s richest woman, she has denied all allegations against her.

Jose Eduardo dos Santos ruled the southern African nation for 38 years. During his regime, he was accused of fraudulently enriching himself and those around him.