JOHANNESBURG — In a continuing shake-up of Angola’s old order, the once-untouchable son of the nation’s longtime dictator has been arrested on corruption charges, state news media announced on Tuesday.

The Angolan government said that José Filomeno dos Santos, the former head of the oil-rich African nation’s $5 billion sovereign wealth fund, had been detained. He had been charged earlier with the fraudulent transfer of $500 million from the fund to an account in Britain.

Mr. dos Santos is the highest-profile figure from the government of his father, José Eduardo dos Santos, who led Angola for 38 years, to face prosecution. During his father’s long rule, which was marked by a nearly decade-long oil boom, the presidential family and close allies amassed great fortunes through their grip on oil, diamonds and other resources.

In the twilight of his presidency, Mr. dos Santos installed two of his children to key economic posts. In addition to his son’s role at the sovereign wealth fund, his daughter, Isabel, already known as the richest woman in Africa, was named to lead Angola’s state oil company, Sonangol.