Authorities in India’s southern Kerala state have issued an alert after a ship carrying oil and hazardous cargo leaked and sank off the state’s coast in the Arabian Sea.

The spill occurred in a Liberian-flagged vessel that capsized near Kochi city on Sunday. The coastal stretch is rich in biodiversity and is also an important tourist destination.

All 24 crew members on board the ship have been rescued but some of the ship’s 640 containers have reportedly been drifting towards the shore, prompting evacuations in the area.

Authorities fear that oil, fuel and other harmful substances that have leaked from the ship and its cargo could endanger the health of residents and marine life.

“As the oil slick can reach anywhere along the Kerala coast, an alert has been sounded across the coastal belt,” a statement from the chief minister’s office said.

Authorities have advised residents living near the sea to not touch any containers or the oil that might wash up to the shore, while fishermen have been asked to avoid venturing too close to the sunken ship.

On Monday, officials said they had intensified pollution control measures to contain the spill.

The Indian Coast Guard has deployed a ship carrying pollution control equipment to the site.

It has also sent one of its aircraft which has an oil spill detection system to survey the area.

The vessel – MSC ELSA 3 – which was travelling from Vizhinjam port to Kochi, began to tilt dangerously when it was about 38 nautical miles from the coast of Kochi.

It capsized into the Arabian Sea in the early hours of Sunday due to flooding in one of its compartments.

The Indian Coast Guard said that the ship was carrying 13 containers of hazardous cargo and 12 with calcium carbide – a chemical that reacts with seawater to release a flammable gas.

“Additionally, [the] ship had 84.44 metric tonnes of diesel and 367.1 metric tonnes of furnace oil in its tanks,” it said.

The crew members were rescued by Indian navy personnel after an hours-long operation.