A senator said Philippine authorities have strong evidence that alleged Chinese spy mayor Alice Guo funded the construction of an illegal Chinese gambling hub in her rural town in the Philippines.

Senator Sherwin Gatchalian said officials have 'irrefutable' proof of alleged anomalous transactions, despite Guo's refusal to answer questions at her Senate interrogation in Manila on September 9.

Speaking to local reporters after the hearing, Gatchalian said: 'The proof is very strong. There are official documents, and those documents have supporting documents. So we have very strong proof. She claims that she knows nothing, but the money went through her account, her personal account. So it is irrefutable that she knew about it.

'Even during her last hearing, she was making a blanket denial. This time around, we have evidence, and we know how the gambling hub was financed. It's basic. Who financed it? We know where the money went through. The next question is who is involved?'

Fuming senators on Monday grilled Guo, who is accused of misrepresenting her Filipino citizenship and being a protector of organised crime syndicates in the sleepy town of Bamban which she had previously governed.

During the hearing, Gatchalian presented money trails allegedly showing billions of Philippine pesos being funneled through Guo's personal bank account and the account of her farm, QJJ Farms.

The dates of the bank transfers reportedly coincided with the construction dates of the Bamban town gambling hub.

Gatchalian said Baofu Land Development, in which Guo has a 50 per cent stake, had paid construction companies Haoli Builders Construction and Maxgear Construction Supply through money from QJJ Farms.

Gatchalian said Haoli Builders was a 'fly by night' company. He added: 'When we went to the office, it was gone. It's said to be a Chinese construction firm. Their clients are Chinese. I guess POGOs. Maybe when this issue became a hot topic, they left.'

The senator was referring to Philippine Offshore Gaming Operations (POGO), casinos notorious for being fronts for organised crime. POGOs cater to Chinese gambling clients in the Chinese mainland, but are notorious for being fronts for criminal activity, including fraud and human trafficking. They mushroomed in the Philippines after former President Rodrigo Duterte cultivated close ties with China during his term.

Alice Guo, also known as Chinese national Guo Hua Ping, was nabbed by Indonesian cops in Tangerang City along the western border of Jakarta in the early hours of September 4. She is the subject of multiple money laundering charges filed by Philippine law enforcement agencies.

Her controversial case stemmed from a raid that uncovered a sprawling Chinese online casino built on land she partly owned in Bamban town.

Guo was last seen in public on May 22. She was dismissed by an anti-graft body and soon went into hiding, refusing to appear before the Senate because 'she was traumatised'.

The mayor sparked fury among locals as she later revealed to have slipped past border checks, travelling through Malaysia, Singapore, and finally Indonesia, where she was caught.

Indonesian police were on high alert following the arrest of Guo's foster sister Shiela and their family friend Cassandra Ong, who both accompanied her while fleeing, in Batam on August 20.

Guo, a newcomer in politics, had insisted on her Filipino heritage in interviews with local media. However, fingerprint matches allegedly found that she was Chinese citizen Guo Hua Ping, sparking outrage and calls for her ouster.

The controversy comes amid the Philippines' territorial conflicts with China over parts of the South China Sea.

Expansionist China currently lays claim over almost the entire South China Sea, one of the world's busiest sea lanes. But a United Nations-backed tribunal in 2016 deemed its claims groundless.

The Communist rogue state - accused of genocide for its crimes against the Uyghur population - has been steadily increasing its influence in recent years through investment in developing countries.