South Korea detected a suspected North Korean hacking attempt Thursday to steal military data by using a journalist's notebook computer, defence ministry officials said.

The military cyber warfare command found that a notebook infected with a malicious code was used in a bid to attack the defence ministry's computer network, a ministry spokesman said.

The notebook belonged to a reporter covering defence, he said, adding notebooks used by reporters are connected to the ministry's Internet network.

There was no loss of data because the cyber command detected the hacking attempt in advance, the spokesman said.

After retracing the IP of the , the command concluded that hackers had used a server in Austria, he said.

"We believe the code has been produced by North Korea, or North Korean hackers are behind today's ," the spokesman told AFP.

The tracked server was used on March 20 last year when hackers attacked South Korean financial institutions and broadcasters, he said. At that time South Korea blamed the North's military for the attack.

In recent years, hackers have used malware deployments and virus-carrying emails for cyber attacks on South Korean military institutions, commercial banks, government agencies, TV broadcasters and media websites.

Investigations into past large-scale cyber assaults have concluded that they originated in North Korea.

The North is believed to run an elite cyber war unit of 3,000 personnel, but it has denied any involvement and accuses Seoul of fabricating the incidents to fan cross-border tensions.