At least 12 people died on Monday after two passenger boats capsized when a block of earth on the bank of one of the main rivers in the Peruvian Amazon collapsed into the water, causing a strong wave, authorities reported.

The accident occurred on the Ucayali River in the early morning hours near the port of Iparia, located more than a day's sail from the capital of the Ucayali region, according to the National Civil Defense Emergency Operations Center (COEN).

The sinking was the result of the "erosion of the banks of the Ucayali River,” it added.

The Mobile Emergency Care System, a public service for medical emergencies, told The Associated Press that 12 deaths had been reported so far and that the number of missing persons remained unknown.

About 20 passengers were treated after being rescued from the water.

Officials said it was unclear how many people were onboard the river transport vessels, as many of these kind of boats operate informally and do not always log the number of passengers.

Most of those affected were from Indigenous communities living along the Ucayali River.

This is not the only river accident to have occurred in 2025.

In May, a collision between a Peruvian navy vessel and a fuel tanker belonging to the Anglo-French oil company Perenco on the Amazon River left two sailors dead and one person missing.

In September 2024, another accident occurred on the Ucayali River after a boat collided with a submerged log, leaving six dead and more than 80 rescued alive.

AP Video shot by Juan Mandujano