Riyadh, Apr 8 (Reuters): Saudi Arabia's public prosecutor has begun investigations and opening arguments in the corruption cases of princes, top officials and businessmen who were detained late last year, an official told pan-Arab newspaper Al Sharq Al Awsat on Sunday.

Authorities rounded up dozens of people in November on Crown Prince Mohammed bin Salman's orders, with many confined and interrogated at Riyadh's opulent Ritz-Carlton Hotel.

Most of them, including global investor Prince Alwaleed bin Talal, were released after being exonerated or reaching financial settlements with the government. But 56 people who had not reached settlements remained in custody and could face trial, the government said late in January.

Saud al-Hamad, deputy attorney general for investigations, told Al Sharq Al Awsat that whoever is charged will be referred to court for prosecution in cases related to money laundering or terrorism. He provided no other details about the suspects.

Hamad said some of those under investigation had failed to respect confidential agreements while others committed further, unspecified, offences.

The anti-corruption campaign is part of Prince Mohammed's push to transform an oil-dependent economy long plagued by graft but now contending with lower global crude prices. But it remains shrouded in secrecy with few specific allegations or details of financial settlements revealed.