Progress Singapore Party (PSP) chief Tan Cheng Bock yesterday described the controversy sur-rounding Workers' Party (WP) candidate Raeesah Khan's social media posts as "gutter politics".

Ms Raeesah, 26, is being investigated after two police reports were made against her for two posts on Facebook in 2018 and this year in which she suggested that the authorities discriminated against minorities.

After news of the police reports surfaced on Sunday, Ms Raeesah, who is a candidate on the WP's Sengkang GRC team, apologised for making "insensitive" and "improper" remarks.

Speaking to reporters yesterday, Dr Tan said whoever made the police reports had timed them to coincide with the campaign period.

"(The posts were made) so long ago, they should have taken action (earlier). Why wait until now? That is my question," he said.

"When it comes to politicking of this nature, let us (take the high road), then the world will look at us and regard Singapore as a mature country."

In the posts, which were made in February 2018 and May this year, Ms Raeesah suggested that police officers discriminated against citizens, and that rich Chinese and white people were treated differently under the law. She also said minorities and mosque leaders were given different treatment compared with church leaders.

Dr Tan said parties should ask themselves if they have conduc-ted their campaign in a "gentlemanly way".

"I don't want to pick an event that happened two years ago. That shows they have been waiting for this moment, and this is what I call gutter politics," he said in an interview after accompanying his party's Tanjong Pagar GRC team on a walkabout at Bukit Merah View Market.

He also accused the ruling People's Action Party of exploiting fear for political gain - what he called the "politics of fear" - pointing out that new Singapore citizens have said they are afraid that their citizenship would be revoked if they voted for the opposition.

"(They) will reward you if you vote for (them), if you don't vote for (them), then you are against (them)," he said, adding that in such a situation, there would be no place for dialogue between both sides.

The PSP team in Tanjong Pagar GRC is led by Mr Michael Chua, 55, who runs a private firm in the environmental sector, and includes lawyer Wendy Low, 43, technologist Harish Pillay, 60, senior trainer Abas Kasmani, 67, and pilot Terence Soon, 29.