Ten Ethiopians are believed to have drowned after a canoe carrying migrants capsized while attempting to illegally cross the Zambezi River from Zambia into Botswana, Zambian officials said Wednesday.

A group of 15 Ethiopians attempted the crossing on Monday night, police and immigration officials said in a joint statement.

Two survivors were arrested, while authorities said 10 people are believed to have drowned. The whereabouts of three other reported survivors were unknown.

Authorities identified the two detained survivors as Ethiopian men aged 33 and 35. They said the younger man had no documents, while the older man had a passport but allegedly failed to present himself to an immigration officer upon entering Zambia.

“At this stage, no bodies have been recovered, and the reported drowning of the 10 individuals remains unconfirmed pending the outcome of the ongoing search operation,” the statement said.

Migrants often use rivers to bypass official border posts across southern Africa. An AFP report documented migrants crossing the crocodile-infested Limpopo River from Zimbabwe into South Africa on makeshift rafts.

The Zambezi is Africa’s fourth-longest river and flows through or along the borders of Zambia, Angola, Namibia, Botswana, Zimbabwe and Mozambique.

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