Today, the Ministry of Manpower warned members of the public about a scam involving suspicious phone calls from someone pretending to be a government officer or from MOM. This caller has been asking people for money to be transferred to an account to "resolve issues related to their stay in Singapore or work pass application." To make things more legit, the number on the receiver's phone will appear as the hotline from the MOM Contact Centre (6438-5122).
Just to be clear, no one from MOM will actually make such calls to you, so if you've received one, go ahead and make a police report. Once again, never give out personal information or make payments to a third party's account through the phone.
Here's the advisory from MOM.