Zambian police say they will increase checks of vehicles at the country’s borders following the discovery over the weekend of the bodies of 27 Ethiopian migrants.
The men – all aged between 20 and 38 – were found dumped by the side of the road on the outskirts of the Zambian capital, Lusaka.
They are thought to have suffocated whilst trying to reach South Africa.
One man found gasping for air was taken to hospital.
In October, the bodies of 25 Ethiopians were discovered in neighbouring Malawi.
The UN says 12,000 migrants have been recorded as missing across Africa since 2014.