Hong Kong ( CNN ) -- At least 36 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 crash happened on a night when Hong Kong 's busy waters were even more crowded than usual , as the city celebrated China 's National Day . One of the 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 . Government officials said the collision occurred off Lamma 's coast at around 8:20 p.m. local time . `` 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 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 . According to the Hong Kong Fire Services Department ( FSD ) , which led the rescue , the vessel sank quickly after the impact . It said low visibility and many obstacles on board 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 and managed to pull 123 people from the water . Twenty-eight people were declared dead at the scene , and eight others were certified dead upon arrival at the hospital , according to a statement early Tuesday from the Hong Kong government . The survivors were taken to five hospitals around the city , with nine said to have serious injuries , the government statement 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 do n't know where my two kids are . '' Residents on Lamma reported being woken up in the middle of the night by the massive rescue operation going on offshore . On Tuesday , the front of the stricken vessel was still sticking out of the water , tethered to a big barge just a few hundred meters from Lamma . Police vessels surrounded the scene , and divers were conducting a search . The authorities have not ruled out the possibility that some people may still be inside the vessel or missing . The passenger ferry was able to dock safely . Government officials have not yet confirmed if passengers aboard that vessel were injured , but Head said nobody around him appeared to have been hurt . The narrow sea lanes leading into Hong Kong 's main deepwater harbor are some of the busiest in Asia , with giant commercial freighters , ocean liners , passenger ferries and private boats of all sizes sharing the same waters . Hong Kong is home to more than 200 outlying Islands , including Lamma , which lies to the southwest of Hong Kong Island -- the city 's financial center . Hong Kong Island is located to the south of Victoria harbor , with Kowloon forming its northern shores . To the north of Kowloon lie the New Territories , which stretch all the way to mainland China . Were you there ? Share your stories , images and videos . CNN 's Judy Kwon , Jethro Mullen , Pamela Boykoff and Mark Morgenstein contributed to this report .
NEW : Impact was like hitting a rock or a lighthouse , a passenger says . NEW : Rescue workers continue to search for survivors near the stricken vessel . Death toll from the accident near Lamma Island rises to 36 , Hong Kong authorities say . Passengers thrown into water ; more than 100 people have been rescued so far .