Indonesian engineers have been under investigation over allegedly stealing technologies related to the KF-21 fighter jet under development, multiple sources said Friday The engineers dispatched to Korea Aerospace Industries (KAI) are under suspicion of storing data on KF-21 development on a USB, according to the sources at the Defense Acquisition Program Administration (DAPA) and Defense Counterintelligence Command. A team of investigators from the National Intelligence Service and the DCC has been looking into data and banned the Indonesians from leaving South Korea. "An investigation is currently under way to figure out whether the stored data contains strategic technologies," a source familiar with the issue said on the condition of anonymity. Indonesia, a partner country of the KF-21 fighter jet development project, has failed to shoulder 20 percent of the project's cost of 8.8 trillion won (US$6.5 billion), raising questions over its commitment over the program launched in 2015. Indonesia is estima ted to have paid 278.3 billion won for the project so far and is behind in payments by nearly 1 trillion won. South Korea plans to begin production of the KF-21 fighter jets later this year, with the aim of deploying 120 KF-21s by 2032. Source: Yonhap News Agency