Six crew members have been arrested after two boats that collided in the waters off Hong Kong on Monday night leaving 37 people dead.

“Police arrested six individuals this afternoon. They are being investigated for endangering people’s lives at sea,” Security Minister Lai Tung-kwok said.

One of the boats was carrying more than 120 people to a fireworks display when it half-sank following the collision near Lamma Island.

The search for survivors is continuing.

The crash happened about 20:30 local time on Monday.

Dozens of people were thrown into the waters as the pleasure boat sank within minutes of impact. The ferry was able to reach Lamma and disembark its passengers as it was taking on water.

The government has confirmed that 37 people died – 32 adults and five children. More than 100 people were injured. The number of people missing is unknown.

Police have arrested three crew members from each of the vessels involved in the accident, the security minister told a news conference.

The head of police, Tsang Wai-hung, said the suspects were responsible for operating the boats.

“From the investigation so far we suspect that the crew responsible for manning the two vessels had not exercised the care required of them by law to ensure the safety of the vessels as well as the people on board.

“We expect further persons to be arrested… The investigation will focus on criminal liability,” he said.

The crash is one of Hong Kong’s worst maritime accident in decades. It occurred during a busy period for passenger travel, at the end of a long holiday weekend to mark the mid-autumn festival that this year coincided with China’s National Day on 1 October.

Power company Hong Kong Electric confirmed that it owned the boat which sank. It was taking staff and family members to watch National Day fireworks in Victoria Harbour.

Hong Kong Chief Executive CY Leung dismissed concerns it would damage Hong Kong’s reputation as a centre of global maritime trade.

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

He said an independent committee would be set up to look into the causes of the crash, and suggest measures to prevent similar tragedies in future.

He declared three days of mourning starting from Thursday, and expressed his sympathies with the victims’ families.

Lamma lies some 3 km (two miles) south-west of Hong Kong island, and is popular with tourists and expatriates.

Hong Kong is one of the world’s busiest shipping channels, but its ferries have a good safety record.

[youtube fEtA9cfC6Og]