Ong Beng Seng (1st L), seen here in 2007, is one of Singapore's richest people
Ong Beng Seng (1st L), seen here in 2007, is one of Singapore's richest people AFP

Singapore's powerful anti-graft body issued an arrest notice for one of the city-state's richest people, his company said Friday, widening a probe into rare high-level corruption.

Hotel tycoon Ong Beng Seng was given "a notice of arrest and has posted bail", Hotel Properties Limited said in a filing with the Singapore Exchange.

The billionaire was asked by the Corrupt Practices Investigation Bureau (CPIB) "to provide information in relation to his interactions" with Transport Minister S. Iswaran, the company said.

Iswaran was ordered to go on leave earlier in the week by Prime Minister Lee Hsien Loong after the CBIB said the minister was "currently assisting" an ongoing investigation.

Lee said the anti-graft body had sought his approval for a formal investigation that would involve interviewing Iswaran, among other people.

The CPIB said it could not disclose details as the investigation was still underway.

Hotel Properties Limited, of which Ong is the managing director, said in its filing that the tycoon had posted bail of Sg$100,000($76,000).

The company owns the Four Seasons and Hilton hotels and also has properties in Australia, Canada, Britain and the United States, according to local media.

Ong, a Malaysian who is a Singapore permanent resident, is credited with helping bring the Formula One Grand Prix to Singapore in 2008.

His private company Singapore GP and the Singapore Tourism Board last year renewed the contract to host the F1 race until 2028.

"Mr Ong is cooperating fully with CPIB and has provided the information requested," the company said.

It added that no charges have been filed against Ong, who was listed by Forbes along with his wife as the 24th richest people in Singapore last year.

Ong, in his late 70s, was allowed to travel overseas from Friday and will surrender his passport to the anti-graft body upon his return, the company said.

Corruption probes involving cabinet ministers are rare in Singapore, which has ranked consistently in international surveys as among the least corrupt countries in the world.