The accident took place yesterday on a highway connecting Dhaka and Khulna town in Faridpur district when the vehicles caught fire as they collided head-on.
"The fire might have occurred by explosion of gas cylinder of the bus. Police and fire fighters rushed the spot and tried to bring the fire under control," Fire service and Civil Defence assistant director Momtaz Uddin was quoted as saying by New Age Bangladesh.
"A Dhaka-bound bus from Narail collided head on with a covered van. We have recovered seven bodies so far and spotted six others. We are trying to bring out the bodies by cutting the smashed vehicles," he added.
At least 20 people were injured in the accident. The collision sparked a huge fire and the toll might increase since some of the injured were in critical condition, he said, adding that the injured have been rushed to nearby hospitals.