India's Coast Guard launched an emergency response on Monday to contain an oil spill after a container ship carrying hazardous materials sank off the southern coast of Kerala, officials said.

The MSC ELSA 3, a 184-metre Liberian-flagged container vessel, sank on Sunday approximately 38 nautical miles southwest of Kochi. All 24 crew members were safely rescued, according to Kerala’s state government.

The vessel was transporting 640 containers, including 13 with hazardous materials and 12 containing calcium carbide  a chemical commonly used in fertilizer production and steel manufacturing. Authorities estimate the ship was also carrying about 370 tonnes of fuel and oil.

“The Coast Guard is actively working to contain the oil spill using two ships, and a Dornier aircraft is spraying dispersants to neutralize the oil,” the Kerala government said in a statement.

India’s Ministry of Defence confirmed the vessel sank due to flooding and expressed concern over the potential environmental impact on Kerala’s ecologically sensitive marine zones.

Officials have placed coastal regions on high alert and warned the public to avoid contact with any containers, several of which have already washed ashore.

The ship was en route between the Indian ports of Vizhinjam and Kochi when it encountered trouble on Saturday and issued a distress call.