The court said all seven defendants had solid evidence to rebut the charges against them.

The department's former director-general Jongarch Bodisunthorn, former deputy director-general Sanchai Kul-preecha and the five other officials were charged with abuse of authority and document forgery.

The Harbour Department is now known as the Marine Department.

The case arose from a contract to purchase canal-dredging boats and related equipment from US-based contractor Ellicott Machine Corporation International for US$49.4 million (Bt1.79 billion). In 2002, the National Counter-Corruption Commission (NCCC) concluded there were irregularities in the purchasing procedures.

After paying $6.68 million to the contractor, the department got only the mothership and some equipment, but not the cutter boats. The contractor was unable to build the cutter ships within the timeframe specified in the contract, which was finally cancelled.

The court yesterday ruled this was not the fault of the defendants, who had evidence to prove that they abided by laws and regulations.

The defendants' friends and relatives in the courtroom broke into applause after the acquittal verdict was read. There was no prosecution representative present.

Public prosecutors have the right to appeal the verdict.