SINGAPORE - Blogger Roy Ngerng has been called up by the police for questioning regarding his participation in a Sept 27 protest at Hong Lim Park, which encroached on a charity carnival being held nearby.

Mr Ngerng, who led the protest along with fellow blogger Han Hui Hui, said in a Facebook update on Tuesday that he had been asked to turn up at the police station "to be investigated for illegal assembly".

Reports from online media sites said police had visited Mr Ngerng at home at 9pm on Monday night and gave him a letter summoning him to an interview at the police complex in Cantonment Road at 2.30pm on Tuesday.

Mr Ngerng also shared a picture of the police letter, which said investigations were being conducted "into an offence of unlawful assembly committed at Hong Lim Park" on Sept 27.

The Sept 27 protest had disrupted a YMCA charity carnival being held at another part of Hong Lim Park, and had scared some special needs children who were performing on stage.

The police have said they have asked "several people" to help them in their probe into the event.

They include Ms Han, who was questioned by the police for seven hours on Oct 10 about the protest.

The police had reportedly also wanted to interview Mr Ngerng but could not reach him as he had been out of the country at the time.