SINGAPORE - Got a call or e-mail that says you won a free air ticket from Singapore Airlines (SIA)?

It may be a scam.

SIA posted an advisory warning about phishing calls, e-mails and websites on Facebook on Thursday (May 25).

"It has come to our attention that there are contests, e-mails and calls that claim to be from Singapore Airlines, which inform recipients of free air tickets, before proceeding to request for their personal data," it said in a post at noon.

"We advise customers to exercise discretion when revealing personal data to unverified sources."

It told customers they should verify these offers of free tickets.

"Please send us details on our social media channels or via this link http://singaporeair.com/en_UK/feedback-enquiry/ and we will get back to you as soon as possible."

They also warned of social media posts and phishing websites that appear similar to the official website singaporeair.com.

Customers who have keyed their KrisFlyer login details on a website other than the official Singapore Airlines website should change their KrisFlyer PIN immediately, SIA added on their website.

Phishing is also used to trick victims into disclosing their credentials. These personal details can be sold or used to access the victim's online accounts.