Vincent Yu / AP

A half submerged boat is lifted by cranes Tuesday, after Monday night's collision near Lamma Island, off the southwestern coast of Hong Kong Island.

Police on Tuesday arrested seven crew members from two boats carrying partygoers that collided, killing at least 38 people in one of Hong Kong's deadliest maritime accidents.

Police Commissioner Tsang Wai-hung said six people, including captains from both vessels, were detained on suspicion of endangering passengers by operating the craft unsafely. "We expect further persons to be arrested," Tsang said. Police announced a seventh arrest after his comments.

Tsang said police suspect both crews had not "exercised the care required of them by law," but he did not offer details.

Salvage crews were raising the Lamma IV, which sank after colliding with a ferry Monday as it carried partygoers to a fireworks show celebrating China's national day.

More than 100 people from the party boat were rescued and sent to hospitals. The ferry was damaged but completed its journey, and some of its passengers were treated for injuries.

The ferry collided with a boat owned by utility company Power Assets Holdings Ltd., which was taking its workers and their families to famed Victoria Harbor to watch a fireworks display in celebration of the national day and mid-autumn festival.

PhotoBlog: Mourning begins as bodies are recovered from ferry crash

Police are interviewing survivors to determine if others were still missing following the accident. Hong Kong Chief Executive Leung Chun-ying has ordered a full investigation into the crash, the worst maritime accident in the territory's waters in 40 years.

Lueng rejected suggestions that Hong Kong needed to overhaul rules governing its busy sea lanes, the South China Morning Post reported.

"This is definitely an isolated incident. The marine territory of Hong Kong is safe," he said.

Dozens gathered at Kwai Chung Public Mortuary on Tuesday looking for relatives, the Post reported.

There was no immediate word about how Monday night's collision occurred on the tightly regulated waterways of one of Asia's safest places, although it appeared human error was involved. The evening was clear and both vessels should have been illuminated by running lights when they crashed near Lamma Island off the southwestern coast of Hong Kong island.

Vincent Yu / AP

Relatives of the victims throw paper money Tuesday as they pay tribute to the ill-fated people aboard a boat that sank Monday night near Lamma Island, off the southwestern coast of Hong Kong Island.

Witnesses Sarah Blackman told the BBC she was on board one of the boats involved.

"I was on the top deck of the ferry and felt the impact — it threw people off their seats. The sound the collision made was horrific," she told the BBC.

"Our ferry cut its engines and a crew member checked if passengers had sustained injuries from the impact. Our engines went back on, and a couple of other passengers and I went back to the rear of our ferry to look for the other boat that was now behind us, and that is when we saw it sinking in the water. As far as I'm aware, no lifeboats were on board — just life buoys and life jackets," she added.

Survivors told local television stations that the power company boat started sinking rapidly after the 8:23 p.m. (8:23 a.m. ET) collision. One woman said she swallowed a lot of water as she swam back to shore.

A man said he had been on board with his children and didn't know where they were. Neither gave their names.

The Associated Press contributed to this report.

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Tyrone Siu / Reuters

Rescuers search for survivors in a partially-submerged boat after two vessels collided in Hong Kong waters on Monday.

Updated at 11:16 p.m. ET: At least 36 people died and dozens were injured when a ferry carrying more than 120 people on a company outing collided with another ferry and sank near an island south of Hong Kong on Monday night in one of the city's worst maritime accidents.

The ferry belonging to the Hong Kong Electric Company was taking staff and family members to watch a fireworks display to celebrate China's National Day and mid-autumn festival when it hit the other ship and quickly began sinking near Lamma island.

Some survivors said people had to break windows to swim to the surface. "We thought we were going to die. Everyone was trapped inside," said another middle-aged woman.

Teams of men in white coats, green rubber gloves and yellow helmets carried corpses off a police launch in body bags on Tuesday. Local media reported that children were among the dead.

More than 100 people were sent to five hospitals and nine people suffered serious injuries or remain in critical condition, the government said in a statement.

The search for victims would continue overnight on Tuesday, the fire department said, because it was uncertain whether there were more people unaccounted for in the incident.

The crash took place at 8:23 p.m. as a boat was traveling from Lamma Island towards the main island of Hong Kong to view the National Day fireworks display.

It was hit by a passenger ferry that regularly travels the 40-minute route between Hong Kong's Central District to Yung Shue Wan, a former fishing village on Lamma that is now favored by tourists and expatriate professionals.

More than 120 people were aboard the Hong Kong utility vessel.

"Low visibility and many obstacles on board" made rescue difficult, according to the fire department.

Many passengers trapped in the flooded upturned ferry before it sank, Reuters reported, citing survivors.

"The rear of the ferry started to sink," a survivor told the Post. "I suddenly found myself deep under the sea. I swam hard and tried to grab a life buoy. I don’t know where my two kids are."

Richard A. Brooks / AFP - Getty Images

A victim is carried ashore by rescue personnel after a ferry carrying about 120 people collided with another commercial vessel off Hong Kong late Monday.

The government initially said a ferry collided with a tugboat.

Later, it said both boats were passenger vessels, but did not give details.

Several local media outlets reported that the second boat was a ferry operated by Hong Kong & Kowloon ferry.

That vessel was carrying about 100 passengers, some of whom were slightly injured, the South China Morning Post, citing Radio and Television Hong Kong.

"Relevant government departments are making all-out efforts to rescue people who fell into the sea after the collision. Senior officials and I will closely monitor the situation. We will do whatever we can for remedial actions,” said Hong Kong's top government official Chief Executive Leung Chun-ying on Monday night.

Reuters and The Associated Press contributed to this report.

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Utpal Baruah / Reuters

Onlookers and rescue workers look at a ferry which was brought ashore after it sank on the Brahmaputra river in the northeastern Indian state of Assam.

An overloaded double-decked ferry carrying mostly farmers and their families capsized in the Dhubri district of the northeastern Indian state of Assam on Monday, killing at least 103 people, police said.

About 100 people were rescued from the ship carrying about 300 passengers, which sank during a storm in the Brahmaputra River, Assam police chief Jayanta Narayan Choudhury told Reuters.

Reports on the number of dead and missing varied immediately after the accident.

People were sitting on the roof of the ferry when it tipped over in a storm in a remote region of the state, close to China and Bangladesh, police said.

"Our rescue efforts have been hampered by bad weather, it is still raining heavily and there is almost zero visibility in the area," P.C. Saloi, a police officer at the scene, told Reuters. Rescue operations were called off late at night and were set to begin again at sun up.

Eyewitnesses told police the vessel was old and broke in two after capsizing in the swollen river, one of Asia's largest. Smaller boats often get into trouble on the river, but the ferry was the largest to sink in recent years.

Reuters

Map of the ferry sinking in India

"I could see people being swept away as the river current was very strong," a witness, Rahul Karmakar, told AFP.

The boat was overloaded with people and sacks of rice, among other goods, and carried no lifeboats or life jackets, the police officer told Reuters..

Prime Minister Manmohan Singh, who represents Assam in the upper house of parliament, said he was "shocked and grieved" by the accident.

Rescue workers said they had contacted colleagues downstream in Bangladesh to help in the search for survivors. 

Reuters contributed to this report.

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