According to reports, the incident occurred when Awami League leaders and supporters were on their way to to attend a party rally at the Suhrawardy Udyan.

Quoting witnesses, DMCH police outpost Inspector Mozammel Haque told bdnews24.com that the bus after coming from Rampura was dropping the Awami League supporters at the intersection right beside the Ministry of Education.
 
At least five bombs went off when the passengers were getting off the bus, he added.

"Prior to this attack, three crude bombs had also been exploded at Karwan Bazar in a bid to create panic minutes after Prime Minister Sheikh Hasina’s convoy passed the area," bdnews24.com reported.