NTUC FairPrice has lodged a police report about rumours claiming its housebrand jasmine fragrant rice is made of plastic.
The rumours, in both English and Chinese, were spread on social media and messaging platforms on Tuesday.
A person had claimed in the message that he has confirmation from a chemist friend that the rice was made of plastic.
Some messages also claimed NTUC FairPrice had agreed to withdraw from its stores all its jasmine fragrant rice, which it had carried for over 10 years.
At 8pm on Tuesday, the supermarket chain posted a message on its Facebook page to deny the rumours.
Mr Jonas Kor, NTUC FairPrice's corporate communications director, told The New Paper yesterday: "FairPrice would like to assure all our shoppers that our rice is safe for consumption, and has passed stringent safety checks by the authorities."
Mr Kor also advised the public to stop circulating the false information which might cause unnecessary alarm.
He added that NTUC FairPrice would be putting up notices at its stores to inform shoppers of the hoax.
When contacted yesterday, a spokesman for the Agri-Food and Veterinary Authority (AVA) said it has not detected cases of fake rice in Singapore.
The spokesman added: "As part of our routine surveillance programme, imported rice is regularly inspected and sampled to ensure compliance with our food safety standards and requirements."
This is not the first plastic rice scare.
In May 2015, plastic rice laced with poisonous resin was said to have entered Asian countries including Singapore.
An AVA spokesman had said then that the rice did not enter Singapore.