An alleged Chinese spy was caught with suspected espionage equipment ahead of the midterm elections in the Philippines.

The suspect reportedly circled the Commission on Elections (Comelec) office in the capital Manila while carrying an international mobile subscriber identity (IMSI) catcher - a machine capable of collecting text messages, mobile numbers, and calls within the vicinity.

Police blocked his rented vehicle on Sunday, April 27, after he was seen roving near other government offices for five days. They found the allegedly spying device still running in the back of the car.

The Chinese tourist claimed he 'did not know' what the machine was.

Ferdinand Lavin, regional director for the National Bureau of Investigation (NBI), said: 'We are not discounting the possibility that the data obtained could be used to affect our elections. Whether they will use the data to influence the outcome of our elections, we cannot say for sure. But we are going in that direction.'

The suspect was taken to the NBI headquarters in Manila, while the IMSI catcher will undergo digital forensic analysis.

Authorities said they were still searching for another Chinese man believed to be the suspect's accomplice.

Comelec chairperson George Garcia said a systems check found no election data was compromised.

The arrest was made as Philippine authorities accuse Beijing of trying to influence the midterm polls this May.

A Senate probe last week reportedly found Chinese-sponsored troll farms hired to manipulate public opinion on social media.

Jonathan Malaya, assistant director general of the National Security Council, said: 'There are indications that information operations being done in the Philippines are Chinese state-sponsored and are actually interfering in the forthcoming elections.'

He added that 'third party individuals and proxies' were being used to 'amplify narratives coming out of Beijing.'

Among the parties accused was the Chinese embassy in the Philippines, which allegedly entered a contract with private company Infinitus Marketing Solutions Inc. to hire 'keyboard warriors' to sanitise China's public image among the chronically online locals.

The Philippines will be holding its midterm elections on May 12.