The attorney general of Venezuela announced on Saturday that 10 officials and 11 businessmen had been detained as part of a growing anti-corruption investigation, and that 11 more people had been handed arrest warrants.

The national oil giant PDVSA, a government agency in charge of overseeing cryptocurrency business, and the courts are the main targets of the probe, which was launched in October. The country’s influential oil minister, Tareck El Aissami, who had worked for the government for 20 years, resigned as a result this week.

“We are talking about one of the most lurid plots in recent years, which involves officials, businessmen who benefited from corruption and young people – including the so-called mafia women – who participated in corruption and money laundering,” Attorney General Tarek Saab told journalists in a press conference.

A Venezuelan entity supervising the use of crypto currency for official transactions was assigned oil cargoes for sale with no administrative control, Saab said. Many of the buyers did not pay for the oil correspondingly, he added.

PDVSA has accumulated $21.2 billion in commercial accounts receivable since 2020 including $3.6 billion potentially unrecoverable, documents viewed by Reuters showed this week, after turning to dozens of little known intermediaries to export its oil under U.S. sanctions.

The 21 people arrested face accusations of appropriation of public assets, money laundering, influence peddling and criminal association. Officials involved could also face charges of treason, the attorney general said.

Venezuela’s President Nicolas Maduro, who said he has been directly overseeing the probe, this week appointed PDVSA’s head Pedro Tellechea as new oil minister, delegating in him the supervision of the whole industry.

In the last five years, Saab’s office has investigated 31 cases linked to corruption in Venezuela’s oil industry, which provides most of the OPEC country’s hard-currency revenue, leading to almost 200 people prosecuted.