As of 21 November, an estimated 622,000 Rohingya refugees fled Myanmar to Bangladesh. The influx began on 25 August, after the Myanmar Army launched security operations in northern Rakhine state. In September, an average of approximately 14,500 people arrived daily. The estimated number of people in need was 1.2 million in the latest Humanitarian Response Plan of October 2017. 

As of 22 September, an estimated 429,000 Rohingya people have arrived in Bangladesh since 25 August. Rohingya started fleeing northern Rakhine, Myanmar as the Myanmar Army is carrying out crackdown operations in the area. Operations, which have killed at least 400 people, started after the Arakan Rohingya Salvation Army carried out attacks against police- and border posts.

Landslides that began on 13 June in Chittagong division have resulted in 160 deaths and 187 injured. 6,000 structures have been destroyed, and other key infrastructure damaged. The area affected is in a region referred to as the Chittagong Hill Tracts (CHT). Reports indicate that approximately 80,000 people across five districts – Bandarban, Chittagong, Cox’s Bazar, Khagrachari and, Rangamati – are affected.

Cyclone Mora made landfall near Kutubdia upazila, Cox’s Bazar district, southeast Bangladesh on 30 May. Initial assessments estimate that over 280,000 people have been affected. Vulnerable settlements where refugees and undocumented migrants and refugees, many of whom are Rohingya, reside in Cox’s Bazar have been hit particularly hard. 

Three border posts along the Myanmar–Bangladesh border were attacked on 9 October by Harakah al-Yaqin, a resurgent group in Rakhine state which has supposed links to the Rohingya. In response, the Myanmar Army has deployed more troops into the northern Rakhine area, mainly in Maungdaw, and has conducted a security operation. At least 130 people have since been killed in raids and skirmishes. A state of emergency has been declared.

Heavier than usual monsoon rains have caused floods in Bangladesh since 20 July. Some 3,200,000 people have been affected and up to 42 have died as of 3 August. Up to 300,000 people have been displaced in 16 different districts, mostly in the Northern and Central provinces (including Bogra, Faridpur, Gaibandha, Jamalpur, Kurigram, Kustia, Lalmonirhat, Madaripur, Manikganj, Nilphamary, Rajbari, Rangpur, Sariatpur, Sirajgonj, Sunamgonj, and Tangail). Most urgent needs are food provisions, WASH, and Emergency Shelter.

Since 13 August continuous rainfall in north and northeastern Bangladesh, together with the onrush of water from upstream, have caused flash floods in low-lying and densely populated areas. More than 800,000 people have been affected, including 500,000 displaced.