Police officers have been deployed across South Africa because of fears that anti-immigration protests could turn violent as President Cyril Ramaphosa urged demonstrators to refrain from “intimidation, threats or ultimatums”.

The protests mark an unofficial deadline set by campaigners for all undocumented foreigners to leave the country.

Many have already fled to escape violence and intimidation. South African police say 25,000 have been repatriated so far. Most are from other African countries.

One undocumented Malawian told the BBC he was “happy to be going back” but “heartbroken” to be leaving behind four young children.

The Ministry of Police said the protests were largely peaceful across the country, with isolated incidents of looting and attempted looting.

Johannesburg, where one of the protests is taking place, is unusually quiet. Shops in the city centre are closed, while police visibility is high on major streets.

Some protesters threw bricks, breaking the windows of some flats in Yeoville, a suburb in Johannesburg where many African migrants live.

Police said that five people were arrested in Johannesburg’s biggest township, Soweto, for allegedly looting a foreign-owned shop.

Five people were also arrested for allegedly breaking into a tuck shop in Hammarsdale in KwaZulu-Natal province.

Many businesses in central Durban, the main city in the province, are also shut. A police helicopter has been circling the city.

Ramaphosa met some of the protest leaders on the eve of the marches in a bid to defuse tensions.

He has repeatedly warned demonstrators to act peacefully, while also accepting the need for immigration reforms.

“Some foreign nationals who live in South Africa are here lawfully,” he reminded citizens in his weekly newsletter, external.

“They work, study, raise families, invest in our economy and contribute positively to our society. They too are entitled to the protection of our laws and our Constitution.

“The right to protest and freedom of expression does not allow people to threaten or intimidate others, or to engage in acts of vandalism or violence,” he wrote.

There are more than three million documented foreign nationals in South Africa, according to official figures.

The statistics do not record the many more migrants believed to be in the country without papers – a bone of contention for the protesters.

Police said that about 50,000 migrants had been arrested since January for being in the country illegally.

A Soweto resident told the BBC that protesters merely wanted foreigners “to comply” with the laws of South Africa.

She said that with the heavy police presence, she did not believe the march in Johannesburg would turn violent.

Another protester, who is part of anti-migrant group Operation Dudula, said they would “push the police to do their” job if undocumented migrants did not leave South Africa.

Nigeria flew out 269 of its citizens on the eve of the protests, bringing to around 600 the number evacuated so far. More evacuations are expected to take place in the coming days.

Ahead of the deadline, thousands of migrants from various countries have been awaiting processing in temporary camps for several weeks out of fear for their safety.

In Durban, which has seen some of the biggest protests, white tents housing mostly Malawians are being dismantled as authorities race to clear the transit camp.

About 7,000 Malawian have already been repatriated, Malawian media report.

Women in colourful sarongs sat on top of their belongings, waiting in line to board a bus home to Malawi.

One man, Nelson Mbewe, said he had gone to South Africa in search of employment to support his family in Malawi.

“But we’ve faced challenges – they’re saying we should go back home because we do not have the right documents,” he told the BBC.

“They say we are Makwerekwere” – a xenophobic slur used to refer to African migrants from other countries – Mbewe said.

“It’s their country, so what can we do? That’s why we have accepted that we just have to [unwillingly] go back home.”

Hassan Phiri, a Malawian who is still waiting to be processed, had a message for the protesters.

“All I want to say to South Africans is that we are all one. No matter what is happening, no matter what will happen, Africa must remain Africa.

“Africa can’t be Africa without South Africa… without Malawi, without anywhere,” he told the BBC, adding: “So whatever will happen, we must love each other and stick together as Africa.”

Anti-migrant marches have been authorised in Durban, Johannesburg and other cities.

The authorities have warned organisers to ensure there is no violence but say they are prepared for any potential disruption.

Police say traditional weapons are not allowed. This could lead to tension between protesters and the police because many of the protesters are ethnic Zulus, and take their shields, whips and sticks when they go on marches.

However, police have so far allowed them to carry the weapons, seizing only a machete at a march in Durban.

According to the government, more than 12,000 immigrants have been deported or repatriated since a wave of protests began earlier this year.

Ghana, Malawi, Mozambique, Nigeria and Zimbabwe have been organising repatriations by air or bus over the last few weeks – with about 3,500 foreigners volunteering to leave.

South African authorities claim more than 500 Nigerians repatriated did not have correct papers, which Nigeria has disputed.

Xenophobia has long been an issue in South Africa, and has sometimes lead to violence.

According to the African Centre for Migration and Society’s (ACMS) xenophobic violence tracker Xenowatch, two people have been killed this year.

In 2008, more than 60 people died during a wave of rioting against non-South Africans.

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