A passenger ferry named Thang Long, which was transporting 200 guests to Con Dao, encountered a technical failure shortly after leaving Vung Tau on the morning of August 1. The vessel, operated by Phu Quoc High-Speed Boat Company, departed from Cầu Đá port at approximately 7:30 AM. However, about an hour into the journey, two of its three main engines experienced issues, leaving only one engine operational.

In light of the situation, the captain made the decision to return to Vung Tau to ensure the safety of all passengers. The ferry, operating at reduced speed due to the malfunction, arrived back at the port around 10:15 AM, with all 200 passengers disembarking safely.

As of noon on the same day, the company had not yet disclosed the specific cause of the engine failures. The vessel underwent a technical inspection before it was set to operate again. Following the return, the company issued refunds to passengers who chose not to continue their journey. Those still wishing to reach Con Dao were transferred to another ferry departing from Trần Đề in Can Tho.

One passenger, Nguyen Van Nghia from Dak Lak, shared his experience, stating that the ferry unexpectedly slowed down and stopped. Initially, he thought it was a temporary halt until crew members announced the engine failure and the need to return to port. Nghia and his wife had planned to visit Con Dao before flying back on August 3, but the incident forced them to change their plans. "We received a refund for the ferry tickets but had to cancel our flight, incurring a loss of over one million VND in fees," he said.

The Thang Long ferry is currently the largest passenger high-speed vessel in Vietnam, operating on the approximately 180 km route between Vung Tau and Con Dao. The ferry measures over 77 meters in length and nearly 9.5 meters in width, with a capacity of up to 1,017 passengers. It is equipped with three MTU engines from Germany, providing a total power output of nearly 12,000 horsepower and a maximum speed of around 33 nautical miles per hour.