DUBAI, Nov 5 (Reuters) - Saudi Arabian investment firm Kingdom Holding reported it swung to a third-quarter profit on Sunday, hours after its billionaire chairman Prince Alwaleed bin Talal was detained as part of a corruption crackdown.

Kingdom Holding, whose investments include stakes in major international firms such as Citigroup and Twitter , said it made 247.5 million riyals ($66 million) in the three months to Sept. 30, compared with a restated loss of 355 million riyals in the same period a year ago.

It reported a 179.9 million riyal profit for the third quarter last year but the company said on Sunday it had restated that figure "to be consistent with current figures". It did not elaborate. Saudi companies moved to internationally accepted IFRS accounting standards this year from a local system.

Profit for the third quarter of this year was boosted by an increase in hotel and operating revenues, larger dividend income, and income and gains on investments, the company said. Revenue increased 76 percent to 550 million riyals.

Prince Alwaleed has been detained by Saudi security authorities, a senior Saudi official told Reuters on Sunday. Saudi-owned Al Arabiya television reported he was detained along with 10 other princes, four current ministers and tens of former ministers in a probe by a new anti-corruption body headed by Crown Prince Mohammed bin Salman.

Kingdom did not release a statement early on Sunday about the detention, and did not respond to requests for comment. (Reporting by Alexander Cornwell; Editing by Andrew Torchia and Paul Tait)