Information security poses a big challenge to Vietnam as the country has been ranked among the top 20 countries in terms of internet user number, an official said here Thursday.

Answering deputies' questions during the ongoing National Assembly meeting, Nguyen Bac Son, Vietnam's Minister of Information and Communication, said most of the technology equipments in Vietnam are imported, which increases the threat to the national information and network security.

From March to June 2013, some 260,000 computers in Vietnam have been infected by Distributed Denial of Service (DDOS) malicious code, a kind of attack attempts to exhaust the victim's resource, Son said.

During the past years, the country has boosted the application of information technology. However, the minister said many of the internet users in Vietnam do not have enough knowledge to protect themselves from risks.

Vietnam in 2011 issued the Circular 27 on coordination of internet incident response activities, including the establishment of Vietnam Computer Emergency Response Team to regularly participate in rescue activities nationwide, as well as asking for international supports.

According to the minister, the investment for information security in Vietnam accounted for only five percent of the total investment on information technology, while only six percent of agencies have emergency response teams.

According to Vietnam Internet Network Center, as of June 2013, the number of Vietnamese internet users reached 31 million, or over 30 percent of the country's population, of which 4.3 million are landline broadband subscribers.