COLOMBO — A huge cleanup operation was underway for the sixth day in Sri Lanka on Tuesday after a container ship laden with chemicals caught fire 12 days ago, inundating the country"s western coastline with microplastic pollution and potentially hazardous waste. Sri Lankan environmentalists said it is one of the worst ecological disasters in the country"s history and have warned of a potential threat to marine life and the fishing industry. Members of the Sri Lanka Navy donned protective suits and rubber boots to remove the plastic pellets, chemical waste and debris that have blanketed beaches near the capital Colombo, including the popular tourist spot of Negombo. The Singaporean-registered ship, called the MS X-Press Pearl, was sailing from India"s Gujarat to Colombo when a fire broke out on board on May 20, as it was nine nautical miles off the Sri Lankan coast. Since then, the Sri Lanka Navy and Indian Coast Guard have been trying to put out the flames and stop the ship from breaking apart or sinking. If that happens, 350 metric tons of oil could leak into the ocean with the potential to cause widespread ecological damage to marine life and affect 30 kilometers (18.6 miles) of coastline between the capital and Negombo, Sri Lanka"s Minister of Fisheries Kanchana Wijesekera said last week. The ship was carrying 1,486 containers when the fire started, 81 of which held "dangerous goods," including 25 metric tons of nitric acid, according to X-Press Feeders, the operators of the X-Press Pearl. The other chemicals on board the ship are yet to be confirmed. On Monday, the Sri Lanka Ports Authority said the vessel"s hull remained structurally intact and "no oil or chemical spill (had been) observed till now." "Salvors are also exploring the possibility of boarding the ship and making a tow connection so it can be moved," the port authority said in a statement. X-Press Feeders said on Monday there were "no visible flames aboard the vessel, though the smoke is still issuing from areas in the ship"s aft," according to the company"s Incident Information Center, referring to the area toward the rear of the vessel. "Firefighting tugs will continue spraying and misting operations to ensure the cooling of all hotspots and the vessel"s hull and hatches, with temperature readings being taken with specialized equipment that has arrived from the Netherlands," it continued. The 25-member crew have been evacuated and most are in quarantine at local hotels. Two crew members sustained leg injuries following an explosion onboard on May 25 and were taken to hospital. One of the pair later tested positive for COVID-19 and was transferred to a special facility in a military hospital, according to X-Press Feeders. The company said it was "helping local police with their inquiries into the fire and are cooperating with investigators." "X-Press Feeders remain fully focused on the ongoing firefighting and salvage operation and will continue cooperating with the relevant investigations into this incident," it said. Sri Lankan authorities have launched criminal and civil probes into how the fire started. X-Press Feeders said it was "too early to tell" but had previously reported one of the containers onboard was leaking nitric acid at its previous stops in Hamad Port in Qatar and Hazira Port in India. The company said: "The advice given was there were no specialist facilities or expertise immediately available to deal with the leaking unit." Concerns for fishermen and marine life The Sri Lankan Marine Environment and Protection Authority (MEPA) said in local media the plastic waste had caused "the worst environmental disaster we have seen in our lifetime." MEPA added the damage from the ship was still being calculated. Muditha Katuwawala, the coordinator of Sri Lankan environmental group Pearl Protectors, said the ocean surrounding the ship would be "quite toxic" and raised fears for the potential impact on marine life, including several local species of turtles and fish. — CNN