Hundreds of guests at an iftar party on Thursday in Gazipur became sick and were admitted to hospitals.
The victims were diagnosed with food poisoning and one of them died on Saturday.
Most of the victims are members of the BNP district unit. Some patients were sent to Dhaka's Cholera Hospital on Sunday as their condition deteriorated. The deceased was identified as Fazlul Haque, 50, of Bangar Khola village.
Tumulia union BNP organised the iftar on the Chuari Khola Government Primary School premises and bhuna khichuri containing both beef and chicken was served. Party members said the food was cooked on the spot and served.
Shourav, one of the food poisoning victims, said more than a thousand people had joined the iftar party. Within two to three hours of the meal many people started vomiting and complaining of stomach pain and dysentery. The sick were rushed to different clinics and hospitals nearby.
According to the admission register at the Kaligonj Upazila Health Complex, 13 people were admitted on Thursday, 49 on Friday, 21 on Saturday and six on Sunday.
Dr Md Masud Rana of Kaligonj Upazila Health Complex said a total of 89 patients were admitted in the hospital due to food poisoning.
President of Gazipur district BNP Fazlul Haque Milon, who also attended the iftar party, said: "We have already held several iftar parties in the upazila but this is the first time that such a thing has happened."
Milon, who appeared to be in good health, said: "We feel sorry for the incident and hope that everyone will be cured soon."