Singapore's Prime Minister Lee Hsien Loong has called for ''respect'' after a resident's racially-charged rant on Facebook caused outrage.
''Let us be mindful of what we say, online and in person,'' Mr Lee said in a post on his Facebook page.
He was responding to public reaction after a woman's comments lashing out at Malays holding weddings in spaces under public housing flats.
The woman has since been fired from her job and issued a public apology.
Amy Cheong made the comments on her Facebook account on Sunday.
One of her posts was laden with expletives and included insensitive remarks directed at the minority Malay community.
Her posts - which have since been deleted - went viral, with more than 10,000 comments and shares, and screenshots distributed on other online forums and blogs.
Ms Cheong was fired from her job on Monday morning and a local newspaper reported that she had left for Australia.
While Mr Lee said he was ''shocked'' to learn of the remarks, he emphasised the incident was ''an isolated case that did not reflect the strength of race relations in Singapore''.
''But it sharply reminds us how easily a few thoughtless words can cause grave offence to many, and undermine our racial and religious harmony,'' he said.
Singapore is an ethnically diverse country, with the majority Chinese making up about 75% of the community, Malays, Indians and people of mixed ethnicities making up much of the remainder.
The South East Asian nation was plagued by ethnic tension and conflicts in its early history in the 1960s.
Several other ministers have also posted their reactions to the incident on their Facebook pages.
Ms Cheong, meanwhile, has issued a public apology, saying that the noise from the wedding - in a common space known as a void deck underneath government-built housing often used for celebrations by different ethnic groups - had caused her to lash out.
"There was no racism intended in my post. I was trying to rest and the noise was affecting me greatly,'' she told a local newspaper, The New Paper.
''I've always been very blunt and vocal, but what I said had nothing to do with race.''
Ms Cheong, formerly an assistant director in the membership department of the National Trades Union Congress (NTUC) - the trade union centre in Singapore, was sacked on Monday morning.
''We will not accept and have zero tolerance towards any words used or actions taken by our staff that are racially offensive,'' Lim Swee Say, NTUC's secretary general, who is also a cabinet minister, said in a statement.
A police report has also been filed against Ms Cheong. A police spokesman told the BBC the matter was being investigated.
This is not the first such incident in Singapore. In the most recent case, two teenagers were arrested in June for posting racist remarks on Facebook.