An investigation into the tragedy has been launched, the island's prime minister says, adding he hopes more will be found alive.

At least 27 people have drowned after a passenger ferry capsized off the coast of Guyana on Saturday night local time. Sixty-nine people aboard the MV Barima had been rescued, Prime Minister Mark Phillips told reporters on Monday, adding 83 more remained missing. Divers continue to search the site where the vessel capsized and people who believe their loved ones may have been on board the stricken vessel have been asked to contact the authorities. "Let me be absolutely clear: where negligence, misconduct or criminal wrongdoing is established, those responsible will face the full force of the law," he said. Guyana's Public Works Minister, Juan Edghill, expressed his anger at a news conference on Sunday, accusing those who operated the ferry of trying to "cheat the system". The official registry had listed 133 as being on board the ferry, but Phillips said on Monday he was now "confident" there were 179 people. Edghill also said the ferry's captain and at least one crew member had tested positive for cannabis. "We have zero tolerance for members of the crew drinking or smoking while at work. And for us to have positive tests from the captain... this is serious," the minister said.