Justice Minister Mmamoloko Kubayi said more than 80 percent of those returned were citizens of Malawi. Authorities did not specify how many people were formally deported and how many accepted voluntary repatriation.

The campaign has been supported by several African governments, which dispatched aircraft and buses to transport their nationals home as anti-immigrant sentiment intensified in South Africa, Africa’s most industrialized economy.

Police said they had arrested 350 people on charges including public violence, intimidation and conducting unauthorized immigration checks after civilians attempted to stop suspected migrants and demand proof of their legal status.

Authorities are investigating the deaths of three migrants—two from Mozambique and one from Malawi—during the recent unrest. Nigeria has also said two of its citizens were killed in anti-immigrant protests, although South African authorities have disputed that the deaths were connected to the demonstrations.

Officials said the deportees and repatriated migrants were primarily from Malawi, Zimbabwe and Mozambique, while smaller numbers came from Nigeria, Uganda and Kenya.

President Cyril Ramaphosa last month announced measures to strengthen border security and tighten enforcement of immigration laws, acknowledging growing public concern over migration while warning citizens against taking the law into their own hands.

The measures followed increasing demonstrations by anti-migrant groups, which have alleged, without presenting evidence, that undocumented immigrants are responsible for high unemployment and crime levels in South Africa.

One of the largest protests took place on June 30, when anti-immigrant groups declared an unofficial deadline for undocumented migrants to leave the country. The government rejected the ultimatum but subsequently saw thousands of Malawian nationals gather at a temporary immigration center in Durban seeking assistance to return home.

South African officials said some migrants left voluntarily, while many others were deported after being found to be living in the country without valid documentation.

Authorities also reported that more than 20,000 migrants were processed through a temporary immigration center established in Musina, a town near South Africa’s northern border.

South Africa has long attracted migrants from neighboring countries because of its comparatively stronger economy, but migration has repeatedly fueled xenophobic tensions. Deadly attacks on foreign nationals in 2008 claimed more than 60 lives, and sporadic outbreaks of violence have continued in subsequent years.

Sabina Tadera of the Southern Africa Network for Immigrants and Refugees said many Malawians who sought repatriation held legal status in South Africa but chose to leave because they feared becoming targets of attacks.

“There is a misconception that all people on the move are undocumented,” Tadera told The Associated Press.

The latest crackdown has also strained relations between South Africa and several neighboring countries, whose governments have criticized what they describe as an increasingly hostile climate toward foreign nationals.

Laura Freeman, an independent human rights and migration consultant, said South Africa has historically attracted migrants seeking economic opportunities unavailable in their home countries, but recurring waves of xenophobic violence risk undermining that reputation.