Singapore's Keppel, the world's biggest oil rig builder, vowed Thursday to put a "painful chapter" behind it as the company revealed a huge fall in profits due to a bribery scandal. US authorities announced in December that Keppel's American subsidiary had agreed to pay $422 million in fines to settle bribery cases. The multi-million dollar kickbacks were paid to Brazilian government officials between 2001 and 2014 in relation to various projects with state-owned oil giant Petrobras and Sete Brasil, a supplier of oil rigs. The news rocked Singapore's corporate world and battered the squeaky-clean image of a country that is usually ranked among the least corrupt on Earth. Keppel Corp. announced Thursday that the group's net profit plunged 72 percent in 2017 after fines and related costs from the bribery scandal. Net profit came in at Sg$217 million ($166.2 million), down from Sg$784 million the year before. It would have risen seven percent without the penalties. "The global resolution reached by Keppel... over past misdeeds in Brazil brings an end to what has been a painful chapter," said the group's chief executive Loh Chin Hua, announcing the company's fourth quarter and annual results. "This is not Keppel. We care not just about results, but also how they are obtained." The company said it had booked one-off penalties and other costs totalling Sg$619 million related to settling the bribery cases. Keppel paid fines to the US, Singapore and Brazil to resolve the cases. Loh said that the company had put in place enhanced compliance controls to prevent any repeat of the scandal. "The board and management are determined to regain the trust that has been lost. We will win business legally and ethically," he said. Singapore's anti-corruption bureau has said it was investigating the individuals involved, but gave no details. Keppel earlier said it had cooperated fully with officials in all three countries and provided its own findings from an internal company investigation after it learned about the problems.