Hundreds of gallons of diesel fuel sank into the waters off the Galápagos Islands on Sunday after a crane toppled onto a barge and caused it to overturn, the authorities in Ecuador said, prompting an emergency cleanup in one of the world’s most revered natural destinations.

The authorities said that 600 gallons were on the barge when it sank off San Cristóbal Island, threatening the nearby environment. They declared an emergency and said they had ordered an investigation.

It was not immediately clear how much fuel had leaked out of the ship, but photos posted on Twitter on Sunday by Ecuador’s Ministry of the Environment showed officials with the Galápagos National Park and the country’s Coast Guard on boats racing to contain the spill.

On Monday, Lenín Moreno, the president of Ecuador, said on Twitter that the spill was under control.

Dramatic video of the crane collapse shows workers trying to load a shipping container onto what appears to be a relatively small vessel called the Orca. As the crane hoists the container over the ship, the container comes crashing down onto the Orca, pulling the crane with it. The crane tumbles over the Orca and into the water, and the ship flips onto its side as people on board dive into the water.