SEOUL - Defence companies in South Korea were raided on July 18 after President Moon Jae In ordered the crackdown on corruptions in the industry.

Prosecutors raided five sub-contractors of the Korea Aerospace Industries (KAI) as part of their investigation into suspected corruption connected to some major defence projects, Yonhap news agency reported.

Computer hard disks, documents, account books and mobile phones were confiscated, said Xinhua news agency, quoting local media reports.

KAI, South Korea's sole aircraft developer and manufacturer, was suspected of overstating production costs and embezzling company funds, said Xinhua.

It was allegedly manipulating spending for developing a utility helicopter known as the Surion, Yonhap reported.

The news agency said that KAI has been involved in other high-profile defence projects, including the development of the T-50 supersonic trainer jet and FA-50 light attack fighter.

The headquarters and Seoul offices of KAI were raided by prosecutors last week, said Xinhua.

The investigation was seen as the starting point of an industry-wide probe on graft.

At a regular meeting with his top aides on Monday, Mr Moon said corruption within the defence industry was "an act benefiting the enemy" and it threatens national security, Xinhua reported.