A 42-year-old Hong Kong housewife has become the biggest victim of a phone scam this year after handing over more than HK$10 million (US$1.3 million) to a man posing as a mainland Chinese police officer.

Her case emerged after 11 people were scammed out of HK$12.4 million over the four-day Easter holiday and amid repeated police warnings about phone scams.

The Discovery Bay resident, surnamed Lee, reported the case to the police on Wednesday.

Lee is a Taiwanese who spent time living on mainland China before moving to Hong Kong. She is married to a professor at the University of Hong Kong.

On the morning of April 14, Lee received a phone call at home from a Mandarin-speaker who identified himself as an officer of the Shanghai Municipal Public Security Bureau. He went on to accuse her of being involved in illegal financial activities.

Lee was ordered to open a bank account in Shenzhen the following day to avoid criminal charges and to assist the police investigation, Apple Daily reported.

Following the instructions of the con man, Lee subsequently made 11 deposits, yielding a total of HK$10.32 million, part of which was borrowed from relatives.

She discovered that the account was emptied shortly after she handed over the bank account number and password to the scammer.

The case came just a week after police issued yet another warning about phone scams and the strategies used by fraudsters.

They said victims were being asked to transfer money into their own mainland bank accounts and reveal their passwords, before the crooks withdrew the funds.

Last Friday, a 23-year-old mainland student studying for a doctorate degree at Chinese University alerted police after he was cheated out of 3 million yuan (HK$3.4 million).