HONG KONG (AFP) -- The wreck of a boat that sank in a collision off Hong Kong, killing 38 people, was examined Wednesday after being hauled to shore as the city sought answers to its worst maritime accident in decades.

The Lamma IV was towed to a beach to reveal a gaping hole in its left rear from Monday evening’s collision with the Sea Smooth ferry, which caused its stern to fill with water within minutes.

More than 120 passengers and crew were on the Hong Kong Electric company vessel to watch a huge National Day fireworks display in Victoria Harbor when the accident occurred just off Lamma, an island to the west of Hong Kong.

The stricken ferry limped to Lamma where its shaken but relatively unharmed passengers disembarked before it took on too much water from a hole in its left hull, which was sheared off in the impact.

Investigators pored over the pleasure boat Lamma IV as they tried to piece together how such an accident could have occurred in one of the world‘s busiest ports, which prides itself on its state-of-the-art transport infrastructure.

“I never thought such a tragedy would happen here and so many people would die,” said survivor Ivan Lee, 47, a building contractor who was on the Lamma IV with his wife and two young children.

“In less than a minute, the boat started to list and the water was coming in... As I put the life jacket over my son’s head, we were already under water.”

“I thought my whole family would die there,” he said.

Lee managed to escape out of a window with his son and daughter. His wife also survived.

Police arrested the captains of both vessels on Tuesday along with five crew members. All of the detainees were released on bail.

Police chief Tsang Wai-hung said the suspects “did not exercise the care required of them by law to ensure the safety of the vessels they were operating and the people on board,” pointing to human error as the likely cause.

Hong Kong chief Leung Chun-ying announced three days of public mourning starting Thursday, when funeral services for the victims are expected to begin.

He also called for an independent inquiry, as the accident raised questions about whether the regional banking hub‘s maritime transport infrastructure had kept up with the huge growth in demand from mainland visitors.

Prakash Metaparti, an assistant professor in Logistics and Maritime Studies at Hong Kong Polytechnic University, said the deadliest maritime accident in the territory since 1971 was probably a case of human error.

“They should be able to navigate even in zero visibility with the radar.

It’s surprising that they didn’t see each other... they should have seen each other,” he said.

“Most likely they misunderstood each other’s intentions.”

He said the crew of the stricken Lamma IV may not have followed basic safety procedures.

“I don‘t think the children were wearing life jackets, and obviously there was no passenger list,” he said.

Passengers on both vessels described scenes of panic and chaos as scores of people were thrown into the water from the Lamma IV. On the Sea Smooth, passengers said crew appeared to have no idea how to respond to the emergency.

At least five children were killed in the collision, officials said. Scores were injured, including some who remain in critical condition in hospital.

“Given our love and dependence on the sea, good has to come from this calamity. The investigation has to lead to even higher standards than the present ones,” the South China Morning Post said in an editorial.

“We cannot help but be shocked and angry. Disasters on such a scale are what we expect in places less developed than ours,” it added.

Ferry operator Hong Kong and Kowloon Ferry Holdings, in its first comments on the collision, said its captain was a 20-year veteran and it would cooperate with the investigation.

General manager Nelson Ng, who lost two relatives aboard the Lamma IV, rejected allegations from Hong Kong Electric executives that the ferry abandoned the sinking pleasure craft.

“We stopped at the scene and did not leave immediately, but what actually happened is up to the investigation to determine,” he said.