They could not return on Thursday as the well-marked low over the northwest Bay and adjoining west-central Bay moved northwestwards and intensified subsequently into a depression, afterwards deep depression and then depression over the North-west Bay and adjoining area.
Among the tourists, there is a group of 300 people from Cox's Bazar called 'Amar Bazar' who went on a three-day trip to the island last Wednesday.
Md Nur Ahmed, chairman of Saint Martin's Island Union Parishad, said there were more than 400 on the Island.
They were scheduled to return Thursday but could not go back due to hostile weather, he said, adding that tourists were told to leave the island on Wednesday but many did not listen.
Teknaf Model Police Officer-in-Charge (OC) Hafizur Rahman said the tourists are safe and that the island's police outpost has been instructed to keep an eye on them.
Teknaf Upazila Nirbahi Officer (UNO) Md Saiful Islam said he is taking regular updates of the tourists.
The authorities concerned and the law enforcers have been asked to take care of the stranded tourists, he added.
St Martin’s, situated a few miles off the coast in the blue waters of the Bay of Bengal, is one of the most beautiful places in Bangladesh. The coral island boasting picturesque sandy beaches, coconut trees and marine life is popular with both local and foreign tourists.