A state defense agency has confirmed that hacking attempts were made on Daewoo Shipbuilding & Marine Engineering and said an investigation is underway.

In a Monday briefing, Suh Yong-won, spokesperson for the Defense Acquisition Program Administration (DAPA) said that related authorities are looking into the matter. 

But Suh declined to comment on whether the attempts were successful, citing the ongoing probe in which officials are still trying to confirm the facts.

The shipbuilder reported the case to the police while military intelligence agencies were also made aware, after which the probe was launched.

But the spokesperson denied news reports saying that hackers suspected to be North Korean attempted to steal research data last year related to South Korea's nuclear-powered submarine development.

Daewoo Shipbuilding has built several domestic warships, including an Aegis-class vessel and submarines.