A Vietcombank customer lost up to VND500 million (USD23,800) after someone used the internet banking service to steal money from her ATM account over one night.

The transactions were made on the night of August 4 and the early morning of August 5 while customer Hoang Thi Na Huong was sleeping. Five consecutive withdrawals of VND100 million happened over night.

After waking up, Huong received Vietcombank's messages about the transactions and the account balance, but not OTP code as usual. She quickly informed Vietcombank of the case and the bank blocked her ATM account immediately.

Headquarter of Vietcombank in Hanoi's Hoan Kiem District

A representative from Vietcombank said to reporters that the bank had a meeting with Huong and her lawyer on August 11. She had entered and logged in her account on a fake Vietcombank bank website on her mobile phone on July 28, 2016, which had allowed her account information to be stolen.

The stolen money was transferred to different Vietnamese banks and then VND200 million was withdrawn through ATM transactions in Malaysia. However, luckily, the remainder of VND300 million had remained within the Vietcombank system, so was retained by the bank.

Vietcombank have co-operated with the customer and management agencies to investigate the case, the representative added.

Vietcombank and other banks in Vietnam have intensified their warnings to customers about their online transactions following the recent cyber-attacks on Noi Bai and Tan Son Nhat airports.

Customers are advised to change the new accounts and cards; not to take photos of cards and store them or share them on email or social networks and carefully check online shops before using their cards. They are also advised not to provide their card numbers to dubious websites.

Customers have been warned to be cautious about promotions and advertisements coming by email, and never access any online shop or make online payment through a link. Instead, they should directly access a site by typing addresses in the browser.