Several hundred protesters yesterday disrupted a charity carnival organised by YMCA at Hong Lim Park by marching through it, frightening special needs children performing on stage and confronting the junior minister present.
Police will be investigating the incident, they said in a joint statement last night with the National Parks Board (NParks).
The rally's organiser, blogger Han Hui Hui, 22, had led the group - gathered to hear her speak about the CPF issue - to march around the park, together with blogger Roy Ngerng, 33, who is facing a defamation suit by Prime Minister Lee Hsien Loong.
The march began after Minister of State for Trade and Industry Teo Ser Luck arrived at the event for YMCA beneficiaries, attended by 900 people.
The marchers, several of whom waved Singapore flags, paused in front of the stage and chanted "Vote them out, PAP" and "Return our CPF" just as a group of special needs children was about to perform a dance item.
The visibly shocked performers from the group Y Stars stopped briefly. Videos of the encounter uploaded on social media drew swift criticism from netizens.
Several protesters also went up to Mr Teo, with one shouting: "Teo Ser Luck, return our CPF."
Mr Teo later told The Sunday Times via SMS that he "had to console one of the handicapped children who was frightened by all the heckling".
Referring to the protesters, Mr Teo told reporters at the venue: "They have their views, which they want to share, and which they voiced out in a different way...
"We must have a listening ear for everybody. Of course, we hope that things could be done in a more friendly manner."
In their statement, NParks and the police said YMCA had applied first to use the park and received approval on Sept 9. Ms Han's application was received last Monday and approved on the same day.
NParks demarcated and allocated space for both events.
"There are two lawns at Hong Lim Park, and each event was allocated a lawn," the statement said.
"NParks and SPF (Singapore Police Force) approached Ms Han to request her cooperation to speak at the allocated space.
"We regret to note that Ms Han did not heed our advice and continued to hold her event at the same lawn as YMCA.
"Ms Han's group encroached into the YMCA event area, holding placards and shouting slogans, disrupted performances and frightened participants, including special needs children who were performing at the charity event."
Ms Han told reporters: "We actually planned not to do anything physical to them. We just wanted to spread our message across."
Madam Regina Aun, 55, manager of Y Stars, said: "While they have the right of expression, it was an event for people with special needs. They could have shown a little more compassion."
Workers' Party activist Bernard Chen said on Facebook yesterday the heckling was "uncalled for" and "the waving of the Singapore flag was shameful and self-righteous".
Manpower Minister Tan Chuan-Jin posted on Facebook last night: "I am appalled. We now heckle special needs children? Vile. Total and absolute disgrace."