Telecom is warning of a scam in which customers are asked to reveal their banking details and hand over control of their computers.
The company says the fraudsters are calling customers pretending to be from Telecom, and leading them to a fake website.
They are then asked to give the caller access to their computer and their personal banking details.
A company spokesperson says anyone receiving such calls should hang up as soon as they realise, without giving any information.
Anyone who may have fallen victim to the scam should call their bank.