ABUJA, Nigeria — Nigeria’s foreign minister has warned that conditions for foreigners in South Africa continue to deteriorate, with no signs of improvement as anti-immigrant violence grips the country.

Bianca Odumegwu-Ojukwu announced additional evacuation flights on Monday, weeks after violent protests against undocumented immigrants began spreading across South Africa.

“There are no signs that the situation is improving,” Odumegwu-Ojukwu said.

Hundreds of Nigerians have already left South Africa, joining tens of thousands of other foreign nationals fleeing the violence. The country has long attracted documented and undocumented African immigrants due to its industrialised economy.

The unrest, which began as protests against undocumented immigrants accused of taking jobs and resources, has escalated to target foreigners with legal documentation. At least four foreign nationals have been killed, while shops owned by immigrants have been burned and looted.

Odumegwu-Ojukwu called on South African authorities to investigate the deaths of two Nigerian nationals, Musa Yunana Joe and Charles Iroegbu, who were killed during the protests.

South African police said Joe’s death did not appear linked to the demonstrations. They acknowledged reports of Iroegbu’s death but could not immediately comment.

Chrispin Phiri, South Africa’s foreign ministry spokesman, asked Nigerian authorities to provide information about their claims. He said the South African government had repeatedly asked Nigeria’s high commission to submit “any actionable information to our law enforcement authorities, which will enable a thorough, objective investigation in accordance with the rule of law.”

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The deaths have drawn attention from foreign governments amid heightened tensions, though South Africa has long struggled with violent crime predating the current xenophobic attacks.

South African authorities have faced criticism for failing to crack down sufficiently on the violence. Observers say the social problems driving citizens to take matters into their own hands stem largely from government failures to provide adequate services.

Pretoria is also embroiled in a separate diplomatic dispute with Ghana following the killing of Ghanaian national Bashiru Isak last week. South African authorities said his death was not linked to the anti-immigrant protests.

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