By Paul Armstrong, CNN October 2, 2012 -- Updated 0042 GMT (0842 HKT) NEW: 25 people are dead, says local hospital authority Two vessels collide between Hong Kong and Lamma Island, says Hong Kong government Hong Kong (CNN) -- At least 25 people have died after two passenger boats collided off Hong Kong's Lamma Island on Monday evening, throwing more than 100 people into the sea. The incident happened as Hong Kong's busy waters were even more crowded than usual, as the city celebrated China's National Day. The accident occurred less than an hour before the city's scheduled fireworks display. Local media reported that a vessel owned by the Hong Kong Electric Company was carrying employees to watch the National Day fireworks display when it was struck by a passenger ferry traveling from Hong Kong Island to Lamma. Government officials said the collision occurred off the seafront of Lamma at around 8:20 p.m. local time. According to a statement from the Hong Kong Fire Services Department (FSD), which led the rescue, the vessel sunk quickly after the impact. It said low visibility and many obstacles on board also made it difficult for rescuers. The FSD said its rescue boats, including a diving support vessel, arrived on the scene at 8:41 p.m. local time. The FSD said 123 passengers were picked up, 17 of whom were declared dead at scene, while eight others were certified dead upon arrival at hospital. Over 100 people were sent to five hospitals across the city, with nine said to have serious injuries or be in critical condition, the FSD added. "After 10 minutes out a boat crashed into ours from the side at very high speed," one male survivor told the South China Morning Post. The rear of the ferry started to sink. 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. Another woman said, "I swam for a long time to reach the surface and swallowed a lot of water. Then I found a rescue boat. CNN's Judy Kwon and Mark Morgenstein contributed to this report. October 2, 2012 -- Updated 0034 GMT (0834 HKT)