Heavy security personnel has been deployed across South Africa because of fears that anti-immigration protests could turn violent as President Cyril Ramaphosa urged those planning to take part to do so without “intimidation, threats or ultimatums”.

The planned protests mark an unofficial deadline set by campaigners for all undocumented foreigner 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.

Johannesburg, where one of the protests is planned, is unusually quiet and all the shops in the vicinity of where marchers are due to gather are closed.

Ramaphosa has repeatedly warned demonstrators to act peacefully and responsibly, 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.

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