Prosecutors on Tuesday raided a defense equipment contractor over alleged corruption involving the delivery of coastal surveillance equipment for the military.

The Seoul Central District Prosecutors' Office said it confiscated contract documents and computer hard drives from the company, identified only by its initial D, which supplied parts to the country's arms procurement agency to establish a complex surveillance system along the country's shoreline.

The system that helps integrate existing radar and thermal imaging devices can be used in all weather conditions and aims to thwart incursions by North Korean boats that sometimes try to covertly enter South Korean waters.

The Defense Acquisition Program Administration has been engaged in the project since 2013 and picked the company as a parts supplier and contractor. The project is worth 41.8 billion won.

Prosecutors suspect that some parts and equipment do not meet mission requirements, and that the evaluation and verification process to designate the contractor has not been carried out in a thorough manner.

A series of shady deals has come to light over the last year since a special investigation team -- comprised of government, military and prosecution officials -- cracked down on corruption in the defense industry.

To continue its monitoring of unlawful activities that has been undertaken by the special team, the government opened a new department under the Seoul Central District Prosecutors' Office earlier this year to cover corruption in the defense industry.

Seoul has vowed to weed out irregularities that can affect South Korea's ability to deal effectively with outside threats. (Yonhap)