The deceased were identified as Ali Nur, 35, son of Firoz Ali and Jamir Molla, 33, son of Golab Hossain of the upazila.
The accident occurred around 7 am at Shantiganj Ahsanmara Bridge area when the Dhaka-bound bus from Sunamganj hit the CNG run-auto rickshaw carrying five people, leaving two dead on the spot and three others injured.
The victims included CNG passengers and the driver, said Abdur Rashid Sarkar, officer-in-charge of Joykalash Highway Police Station.
They met the tragic accident while returning to their respective village after attending an Urs-Mahfil in Biswanath upazila of Sylhet district, reports UNB.
The injured were taken to Sunamganj Sadar Hospital.