Peruvian officials are still searching for four members of an Aqua Expeditions cruise ship that exploded and sank in the Amazon River Saturday during a restocking mission.

According to a company statement, the 24-passenger Aqua Amazon “suffered a very serious accident… that caused an explosion and resulted in the sinking of the ship.”

There were no passengers aboard the Amazon during the time of the incident but of the 17 crew members aboard, four are still missing and several others were rushed to the hospital to treat injuries according to Travel Market Report.

"All efforts are being made to get a better understanding of the status of the missing crew.  The entire operations team is on the ground providing logistical support with local emergency services,” said Aqua Expeditions founder and CEO Francesco Galli Zugaro.

The ship’s next sailing was scheduled for July 16 but passengers affected have since been reassigned to the Expedition’s Aria, a slightly larger vessel that debuted in 2011. The company's offices in Lima and Singapore were open Sunday to assist clients with future Amazon bookings. Founded in 2007, Aqua Expeditions specializes in smaller, luxury river cruises in South America and Southeast Asia. Aqua Expeditions' fleet now includes two luxury river boats: Aria Amazon in Peru, and the Aqua Mekong which takes guests down the Mekong River in Vietnam and Cambodia.  

This is the second fire-related incident to occur on the Amazon River this year. In April, two American tourists died on an International Expeditions ship, after a fire broke out in their cabin and the couple were unable to escape. No one else aboard that ship was injuired. International Experiditons is not affiliated with Aqua Expeditions.

Local authorities are continuing to investigate the Aqua Amazon tragedy.