Text messages that advertise apartments in newly constructed buildings annoy Vietnamese mobile phone users. — Photo sgtiepthi.vn

The messages are not sent by mobile network operators, but from different Sim cards.

Nguyen Thi Ha, a MobiFone subscriber in Ha Noi, says that her mobile phones are bombed with spam text messages every day. "I receive about seven messages advertising newly built apartments per day. My office colleagues too receive similar messages and feel bothered," she says, adding that the number of text messages increase at the end of the year, when more people want to purchase apartments.

Spam is a hot topic in popular forums in Viet Nam. On Vietnamese auto forum otofun.net, a member posted a photo of his mobile phone inbox filled with spam text messages. He said that he received a maximum of 30 unsolicited messages, even though he had blocked their phone numbers and forwarded them to the SpamAlert system, operated by the Vietnam Computer Emergency Response Team (VNCERT), which allows users to report spam by forwarding them to +456.

Golden_Coin, a member of Vietnamese auto forum otofun.net, uploaded a photo of spam text messages in his mobile phone inbox.

Nguyen Quoc Khanh, general director of DTJ Investment and Distribution JSC, says that a company authorised by the information and communications ministry is in charge of advertising its new apartments via SMS. He says that there are customers who like to read text messages and those who don't, and the latter can refuse to receive messages from the firm.

Meanwhile, Tran Duc Dien, director of Maxland's property trading floor, told the Vnexpress news website that enterprises do not get involved in SMS marketing, but real estate brokers do.

"Leaders find it hard to control selling and introduction of products by employees. The lists and mobile phone numbers of customers are all owned by them," he said.

Dien pointed out that enterprises do not encourage their employees to use spam text messages as a way of promoting products. However, real estate brokers use spam because they consider it as an effective method, he added.

According to the VinaPhone mobile network, till December 15, it had locked more than 689,000 Sim cards and 81 nationwide numbers beginning with 1900xxxx and 6/7/8xxx for spamming.

Till the end of November, the ministry had detected and fined digital content providers VND1.375 billion (more than US$65,400) for sending spam text messages. In October alone, the fines amounted to VND1.185 billion (more than $56,400). — VNS