SINGAPORE - If you are a user of WhatsApp, be careful of messages with unusual requests, even if they have been sent by your contacts.

The Singapore Police Force warned on Wednesday (April 18) about recent cases of people who lost access to their WhatsApp accounts which had been taken over by scammers.

The police said victims would first receive WhatsApp messages from their contacts requesting WhatsApp account verification codes. These contacts' WhatsApp accounts are believed to have been compromised.

Once the victims send the verification codes to the scammers, they would lose access to their WhatsApp accounts.

In other scams reported overseas, scammers used compromised accounts to deceive account holders' contacts into purchasing gift cards and sending over passwords for the cards. These gift cards were then sold online.

The police have advised members of the public to be wary of unusual requests received over WhatsApp, even if they are from contacts. They should always call their contacts to verify the authenticity of the requests, said the police.

Users can protect their WhatsApp accounts by enabling the "Two-step Verification" feature, which is found under "Account" in the "Settings" tab of the WhatsApp application. This feature would prevent others from compromising their WhatsApp accounts.

Those with more information on such scams can contact the police hotline on 1800-255-0000, or dial 999 for urgent assistance.

Members of the public can also seek advice from the National Crime Prevention Council by calling its anti-scam helpline on 1800-722-6688 or visiting www.scamalert.sg