Authorities in Colombia are investigating claims that US mining company Drummond dumped coal into the Caribbean off the coast of the South American country, officials said Tuesday. On January 12 and 13, Drummond workers dumped a load of coal into the sea off the northern port of Cienaga to prevent their barge from sinking, alleged Captain Guillermo Diaz, head of the local maritime authority. \"Photographs show there was dumping of coal into the sea. We are determining the exact amount by means of an investigation,\" Diaz told local media. Those probing the matter include the country\'s national environmental licensing authority, the national mining agency and the energy ministry. Environment Minister Juan Gabriel Uribe said Drummond could face a $1.6 million fine and other sanctions for not reporting the alleged incident in time. Drummond, based in the US state of Alabama and present in Colombia since 1998, declined to comment. \"Drummond will not comment while this matter is under investigation by the Colombian authorities,\" spokesman Paulo Gonzalez told AFP in an email.