The powerful cyclonic storm Mahasen finally hit Bangaldesh's Patuakhali district on Thursday morning, creating havoc with heavy showers and strong winds lashing at a speed of 100 kmph.
The storm has been categorised as class 1 storm and authorities have issued a high alert in low-lying areas of Chittagong and Cox's Bazar Noakhali, Laxmipur, Feni, Chandpur, Borguna, Bhola, Patuakhali, Barisal, Pirozpur, Jhalokathi, Bagherhat, Khulna, Satkhira.
Thousands of people sought refuge in the temporary cyclone shelters, after being evacuating from their houses in the low-lying areas.
"Over 100,000 people will be evacuated from the remote islands of the district by Wednesday evening" said Deputy Commissioner of Patuakhali District to Xinhua.
The government issued Danger Signal No 7 on a scale of 10 to all the districts lining the northeastern coasts and warned people to stay away from there. Possible landslides are also expected at places due to the continuous rainfall.
However, Shamsuddun Ahmed, deputy director of the Bangladesh Meteorological Department, told AFP, "It is not a severe cyclone".
Some areas have reportedly submerged into waist-deep water with blackouts.
Four people have been killed so far with one person being drowned and another being hit by a tree, reported Agence France Presse.
The Bangladesh government said they are well equipped with army and defence forces ready to launch operations.
Earlier, the Disaster Management Ministry had informed that over 50,000 volunteers have come forward to help the government.
Meanwhile, neighbouring Burma continued facing the tense situation of shifting displaced refugees as a boat carrying 50 victims was reported missing.
While officials of the Myanmar government announced that 166,000 people have been relocated, UN has clarified that the shifting process was delayed owing to the unwillingness of many refugees.
Out of the thousands of displaced Rohingya muslims, victims of the ethnic clashes, only a small number has been shifted from the temporary camps.
Kirsten Mildren, from the UN Office (Ocha) told BBC that the shifting process was, "not moving as fast as we'd like - it's certainly a race against time. We're finding it very difficult to convince [people] to move to higher ground or safer buildings".
A 'Red Emergency' has been issued in the area, which is the highest of threats for tropical cyclones.
While the effects of Mahasen caused incessant rains in the state of Meghalaya on Thursday, an alert has been issued in Assam. Fishermen have been warned to stay out of the waters of the Brahmaputra and ferry services have been stopped for the time being.