Eighteen people have been arrested after dawn raids smashed what police say is a large-scale illegal immigration ring in London.

Officers from the Metropolitan police, supported by Essex police and immigration officials, targeted two businesses being run as colleges, along with ten homes, in east and south London and Essex.

The arrests have been made on suspicion of conspiracy to facilitate illegal entry and leave to remain in the UK and money laundering.

The 18 arrested people are being kept in custody at various London police stations.

Police said the alleged deception involved fake documentation claiming students were studying at one of two London colleges, so they could remain in the UK.

Most of the immigrants targeted by the alleged scam were South Africans.

The operation, codenamed Taming, also involved co-operation with South African police in Durban.