Hong Kong (CNN) -- Hong Kong authorities announced an investigation Tuesday into the collision of two passenger boats that killed at least 38 people in the territory's deadliest ferry accident in recent memory.

investigation into：有关...的调查

The crash happened Monday evening, a night when Hong Kong's busy waters were even more crowded than usual, as the city celebrated China's National Day.

Police said they have arrested six crew members from the vessels on suspicion of endangering passengers.

Search and rescue efforts will continue for at least two more days as authorities look for missing passengers, authorities said Tuesday. They did not know exactly many are unaccounted for.

unaccounted for：下落不明的

One of the two vessels, owned by The Hong Kong Electric Company, was carrying company employees and their families to watch the scheduled fireworks display when it was struck by a passenger ferry traveling from Hong Kong Island to Lamma Island.

Lamma Island：南丫岛

Government officials said the collision occurred off Lamma's coast around 8:20 p.m., plunging more than 100 people into the water.

plunge into：跳入

"I thought we'd hit a rock or a lighthouse," said Chris Head, a school teacher who was on the passenger ferry that crashed into the Hong Kong Electric vessel. He said the ferry went from what felt like full speed to "an abrupt halt."

crash into：闯入；撞到...上

Head said the force of the impact threw him out of his seat at the back of the ferry, which was not very full of people.

As the damaged ferry began to move toward the pier in the small town of Yung Shue Wan on Lamma, Head said he could see the other boat had started to sink into the water vertically, like the Titanic.

Yung Shue Wan：榕树湾

"It was very dark," he said. "There were very few lights on board."

According to the Hong Kong Fire Services Department (FSD), which led the rescue, the vessel began to sink quickly after the impact. It said low visibility and many obstacles on board made work difficult for rescuers.

Hong Kong Fire Services Department：香港消防处

low visibility：低能见度

The FSD said its rescue boats, including a diving support vessel, managed to pull 123 people from the water.

diving support vessel：潜水支援船

The death toll would appear to make the crash Hong Kong's most lethal maritime accident since 1971, when 88 people died after the ferry Fat Shan capsized between Hong Kong and Macau amid a typhoon.

In 2008, 18 Ukrainian sailors died in 2008 after their boat hit a Chinese cargo ship and sank.

回顾：【读报笔记】系列>>

点击查看口译备考专题，阅读更多相关文章！