Nine foreign nationals have been arrested in South Africa after they were allegedly caught trying to leave the country to fight in the war between Russia and Ukraine, police said.

The group, whose members are aged between 20 and 26, was detained on Sunday evening in and around Johannesburg by a multidisciplinary team. Authorities said the suspects were caught as they were "preparing to board flights out of the country", although their final destination remains unclear.

According to police, the arrests took place at OR Tambo International Airport, the country's biggest airport, and at a hotel in Bruma, east of Johannesburg. The operation involved Interpol, the international police agency.

The group is accused of contravening South African laws that outlaw mercenary activity without government permission.

In its statement, police said the involvement of Interpol and other international law enforcement agencies indicated that the suspects had also allegedly violated laws in their respective home countries, prompting cooperation with South African authorities. Officials declined to reveal the nationalities of those detained but confirmed that none of them lived in South Africa.

Authorities have also not said whether the men allegedly intended to fight for Russia or for Ukraine, and gave no details about the organisations suspected of facilitating their travel.

The arrests come against the backdrop of a wider recruitment drive drawing Africans into the conflict. Citizens of several countries on the continent, including Kenya, Ghana and South Africa, have gone to fight for Russia in Ukraine, with some saying they had been duped and had not realised where they were going. A Ukrainian intelligence assessment earlier this year estimated that more than 1,700 people from 36 African countries had been recruited to fight for Russia.

Kenya estimated at the time that 252 of its citizens had been illegally conscripted in Russia. In March, Foreign Minister Musalia Mudavadi travelled to Moscow to raise the issue and said an agreement had been reached to stop the recruitment of Kenyan nationals.

Ghana said in February that 55 of its citizens had been killed in the conflict, with 272 believed to have been lured to fight since the war began in 2022. That same month, South Africa secured the return of 17 of its nationals who were allegedly tricked into joining the war, while in December last year South African authorities arrested five people, including a journalist, for allegedly recruiting fighters. Ukraine has also recruited foreign nationals, including from Africa.

The nine suspects are expected to appear in court on Monday or Tuesday.