LABUAN BAJO, Indonesia — A traditional phinisi tourist boat carrying 13 tourists sank near Labuan Bajo, East Nusa Tenggara, on Sunday morning after striking a shallow coral reef, authorities said.

All 13 tourists — seven foreign nationals and six Indonesians — and six crew members were safely evacuated. No injuries or fatalities were reported.

The vessel, identified as KM Yukai, was heading from a mooring area near Kelapa Island toward Bidadari Island for a snorkeling trip when the incident occurred at around 6:30 a.m. local time on Sept. 27.

According to West Manggarai Police, the boat was passing near Tanjung Sture during low tide when it struck a shallow coral formation.

The impact damaged the hull, allowing seawater to enter the vessel. The boat began listing heavily and eventually sank.

As the situation worsened, passengers who had been inside the cabins were instructed to move outside. They were then evacuated using lifeboats and transferred to another tourist vessel, Alfatran.

The Labuan Bajo Harbourmaster and Port Authority, known as KSOP, later deployed a Sea Rider to assist with the evacuation.

All 19 people on board — 13 tourists and six crew members — were eventually brought safely to Marina Labuan Bajo.

Authorities have since opened an investigation into the circumstances surrounding the sinking.

Police said the captain and a crew member responsible for steering the vessel were being questioned as investigators examine possible negligence.

Preliminary information indicated that the captain may have failed to properly identify the shallow reef and navigational markers in the area. However, the investigation remains ongoing and authorities have not announced a final determination of responsibility.

Material losses from the sinking were estimated at around Rp1 billion (approximately US$60,000).

Authorities were also coordinating efforts to secure and recover the sunken vessel to prevent it from becoming a navigational hazard for other boats.

Labuan Bajo is one of Indonesia’s major tourism gateways and a primary departure point for boat trips to the islands and waters surrounding Komodo National Park.