Door open with loud alert signal, passengers alight from and to metro

Door open with loud alert signal, passengers alight from and to metro train. View from within carriage, side perspective along wagon interior. Chinese commuters come inside car, sliding doors close. POV camera, First Person View from passenger eye. Mass Transit Railway, Hong Kong subway rapid transportation system, Island line. Train has arrived to station platform, commuters quickly alight and board, and train ready to depart.