Nhlanhla Lux Dlamini, the leader of anti-migrant protest in South Africa has been arrested.
The black activist in his 30s was taken to Johannesburg's central police station "for questioning," a police spokesman told AFP but did not give details.
This arrest immediately sparked reactions from members of his movement, who threatened on social networks and in the media to intensify their operations.
Since January, demonstrations to "defend the future of South Africans" and against migrant workers have been held regularly in several cities.
Protesters have been visiting shops to demand that foreign employees accused of "stealing South Africans' jobs" be fired. These rallies have so far led to tensions but not to violence.
Hundreds of Nigerians are reported to have left the country out of fear of being attack.
South Africa is periodically plagued by xenophobic outbreaks. Sixty-two people were killed in riots in 2008. Violent clashes broke out in 2015, 2016 and in 2019.
The country has 3.95 million foreigners out of nearly 60 million inhabitants, according to official statistics. The continent's leading industrial power struggles with 35% unemployment but attracts many African migrants.