Police arrested 21 Malaysians after they were caught staging an outdoor protest at the Merlion Park at 4.50pm on Saturday.
This despite earlier police advisories that such gatherings are against Singapore's laws.
"The police would like to reiterate (that) while foreigners are allowed to work or live here, they have to abide by our laws," said a police spokesman in a statement on Saturday.
"They should not import their domestic issues from their countries into Singapore and conduct activities which can disturb public order, as there can be groups with opposing views. Those who break the law will be seriously dealt with,"
The arrest comes after warnings were issued to nine Malaysians for "actively participating in the illegal gathering" at the Merlion Park on Wednesday, where a crowd of about 100 people had gathered to protest against the recent Malaysian election results.
Read here :Sunday Times