The traders were returning to their neighbourhood after buying vegetables from the wholesale market in Manikganj’s Jaagir.
Police said the locals reported an abandoned black suitcase that was found to contain the body when opened.
“There are wound marks on the body,” said Shahbagh police’s sub-inspector Shafiyar.
Police suspect the boy was as a domestic help and was murdered.
The body has been kept at the DMCH morgue.