Some netizens suggested that a doctor's attempt to save a man who collapsed at a hawker centre had been staged to win votes.
The doctor was People's Action Party (PAP) candidate Koh Poh Koon.
Opposition politicians then jumped in to decry the cynicism.
Said People's Power Party secretary-general Goh Meng Seng: "Give credit where credit is due, people should appreciate what Dr Koh has done instead of politicising the event."
Singapore Democratic Alliance chief Desmond Lim added: "We should praise Dr Koh for reacting immediately to save a life. Such things should not come with political colour.
"It's a proper and appropriate reaction when you see someone in need of help, so I don't think he was thinking about votes or what people would say."
Both party leaders also said that political parties should take the opportunity to educate their supporters to see things rationally and not make inappropriate comments.
The incident happened yesterday at the Ang Mo Kio Central Market & Food Centre.
Madam Chin, 58, a stall assistant at the food centre said: "The man collapsed near my stall and we wanted to go to the nearby clinic to get help but it was not open on Sunday.
"Someone then ran to call Dr Koh who had just walked past the food centre."
She said he returned and performed cardiopulmonary resuscitation (CPR) on the man, who looked to be in his 70s, and stayed to help the paramedics who arrived soon. An ambulance was at the scene within eight minutes of receiving a call at 7.57am.
The man, who was suspected to have had a heart attack, died at 10am at Khoo Teck Puat Hospital.
A video and pictures of the act were uploaded online and some netizens praised Dr Koh as a "Good Samaritan".
Dr Koh, 43, is part of a six-member team helmed by Prime Minister Lee Hsien Loong contesting Ang Mo Kio GRC in Friday's General Election.
Family doctor Leslie Tay said the negative comments were unwarranted.
He added: "It's someone's life. He was just trying to do what he was trained to do, which is to save lives.
"I'm sure if he didn't help, people would also comment on that. But I think Dr Koh has no regrets, because any doctor would have done the same."
Dr Koh could not be reached for his comments. When approached by The Straits Times, he declined to be interviewed and would only say: "We should not politicise this. Let's give the family the privacy to grieve."
Political observers said the attempt to politicise Dr Koh's act was just another indication that some aspects of campaigning have turned nasty.
Other incidents include campaign posters that have been torn down, others that were defaced with paint and members of the audience who heckled independent candidate Han Hui Hui at her rally on Thursday night.
Referring to Singapore's political culture, Singapore Management University's Associate Professor Eugene Tan said political leaders and party supporters all play a part in developing a wholesome political landscape.
He said that such nasty incidents might just be mischievous minds at work and might not be affiliated with any particular party, but social responsibility needs to be practised especially during this campaigning period when emotions run high.
Referring to Dr Koh's act, he said: "No one should believe that this is a stunt, especially in a life-and-death situation like this."
This article was first published on September 7, 2015.
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