Nigeria's high commission in South Africa has urged its citizens there to be cautious following an anti-illegal immigration protest in Eastern Cape province that turned violent.

On Monday, activists were holding a peaceful march in the port city of KuGompo (formerly East London). But disorder erupted after a protester said he was attacked by a foreigner, prompting demonstrators to damage several vehicles and shops.

The trouble came amid tension over the recent installation of a Nigerian community leader in the city, who has a traditional title that can be translated as "king of the Igbo people in East London".

Some South Africans in the local area saw this as an attempt to grab political power.

Traditional leader Xhanti Sigcawu, who was present at Monday's march, told broadcaster Newzroom Afrika the installation ceremony had left local chiefs feeling "undermined" as the area was the "territory of the Xhosas".

South Africa is home to about 2.4 million migrants, just less than 4% of the population, according to official figures.

Most come from neighbouring countries such as Lesotho, Zimbabwe and Mozambique, which have a history of providing migrant labour to their wealthy neighbour. A smaller number comes from Nigeria.

Xenophobia has long been an issue in South Africa, which has been accompanied by occasional outbursts of deadly violence, and anti-migrant sentiment has become a key political talking point.

The South African authorities, including KuGompo mayor Princess Faku, condemned Monday's trouble, which saw 10 vehicles set alight and local and foreign-owned shops looted.

"We supported the march because it is part of the efforts of defending our sovereignty, but we cannot condone violence. Violence doesn't solve problems… It's very sad that such an important march was turned into violence and chaos," Faku, who belongs to the African National Congress, said.

No arrests have been made.

The Nigerian high commission urged its citizens to limit movement and avoid public gatherings while tensions remain high.

The protest was organised by various civil society groups and political parties.

A fortnight ago, Solomon Ogbonna Eziko was recognised as the "Eze Ndi Igbo East London" by members of the local diaspora.

Installing an "Eze Ndi Igbo" is a common practice among Igbos living away from home.

The Igbo people, prominent in Nigeria's south-east, are one of the country's largest ethnic groups and are prominent in the diaspora.

While members of the Igbo community in KuGompo have recognised Eziko as their leader, his title is ceremonial and has no political meaning or cultural significance outside his community. Within the grouping, he is recognised as a mediator in minor disputes and is invited to local ceremonies.

A leader of South Africa's Igbo community, Dr ABC Okokoh, confirmed this, explaining to national broadcaster SABC that the ceremony recognising Eziko was a "private event".

"We are not here to establish a kingdom [or] a king because there are laws in this country that must be respected," he said.

He apologised for the "consequences that played out" as a result of the event.

Some South African cultural experts condemned the installation of Eziko as unlawful and a violation of customary protocols.

The Eastern Cape's cooperative governance department, which oversees traditional affairs in the province, distanced itself from the event and called for the respect of the country's laws.

During a picket by civil society groups in Pretoria on Tuesday at Nigeria's high commission, a diplomat also apologised to South Africans for the developments that followed Eziko's recognition.