The bodies of 27 people, believed to be migrants from Ethiopia, have been “dumped” by the roadside in Ngwerere area north of Zambia’s capital, Lusaka.
They likely suffocated to death while in transit, Police Spokesperson, Danny Mwale, told the BBC.
One survivor found “gasping for air” has been rushed to a local hospital, he said.
Zambia is a transit point for migrants, mostly from the Horn of Africa, who want to reach South Africa.
Mr Mwale said residents of Ngwerere found the bodies on Sunday at 06:00 local time (04:00 GMT).
He said the police believed the migrants were Ethiopian nationals based on the identity documents found on them.
“Our preliminary investigations indicate that a total number of 28 persons, all males aged between 20 and 38, were dumped in Meanwood Nkhosi along Chiminuka road in Ngwerere area by unknown people,” the police said in a statement.
The bodies have been taken to Zambia University Teaching Hospital mortuary.
In neighbouring Malawi, the authorities discovered 25 bodies of Ethiopian migrants in a mass grave in October.
The stepson of Malawi’s ex-President, Peter Mutharika, has been arrested after 30 bodies were found in graves in a forest in October, police have said.
The corpses were of boys and men believed to be Ethiopian migrants being trafficked to South Africa.
Police said there was strong evidence linking Tadikira Mafubza to the graves, and a vehicle suspected to have been used to transport the group has been also impounded.
Mr Mafubza has not yet commented. But the former governing Democratic Progressive Party (DPP) has described his arrest as a political witch-hunt against Mr Mutharika’s family and his supporters.
Police found a mass grave with 25 bodies, and graves with five other bodies in a forest in the northern district of Mzimba in October after young boys reportedly detected a foul smell.
The bodies were exhumed, but the authorities have not yet disclosed the results of autopsies. -BBC