Prosecutors said Friday they have raided the Seoul office of POSCO, the latest in a series of investigations into alleged corruptions involving South Korea's top steelmaker.

Prosecutors confiscated accounting books, internal documents and computer hard disks at the Seoul office. POSCO's headquarters is in Pohang, about 370 kilometers southeast of Seoul.

The raid came hours after prosecutors secured accounting books and other internal documents from Dongyang Construction, a small builder in Pohang, and its five affiliates.

Dongyang Construction is suspected of creating slush funds for POSCO and its affiliates. The construction company won about 10 overseas projects placed by POSCO since 2009 when Chung Joon-yang began to serve as CEO of POSCO.

In April, prosecutors raided the head office and factory of Kosteel Co., which buys steel slabs from POSCO to make wire rods.

Prosecutors believe the Kosteel chairman, who is known to be friends with Chung, helped the global steel giant evade taxes by doctoring its transaction records since 2007. (Yonhap)