The deceased have been identified as Md Jahidul Islam, his wife, and their son—residents of Ishwar Ghat village in Dhunat upazila of Bogura.
The identity of the fourth victim is yet to be confirmed.
The accident occurred around noon at Barachala on the Mawna-Kaliakoir regional road, said Abdul Mannan, Officer-in-Charge of Kaliakoir Police Station.
According to police, the autorickshaw was travelling towards Kaliakoir from Mawna with five passengers on board.
As it reached Barachala, a covered van coming from the opposite direction rammed into it, killing Jahidul and his son on the spot.
Locals rescued Jahidul’s wife and another injured passenger, initially taking them to Kaliakoir Upazila Health Complex.
They were later transferred to a hospital in Mawna, where doctors declared them dead upon arrival, reports UNB.
OC Abdul Mannan said the covered van has been seized and legal proceedings are underway.