Six home affairs officials were arrested in the Vaal Triangle on Friday following an investigation into the fraudulent issuing of documents, the department said.

"This is part of an ongoing investigation that started some time ago," the department's integrity management unit chief director, Sulleiman Hancock, said in a statement.

The arrests were in connection with the alleged unlawful issuing of birth certificates, identity documents and passports.

Hancock said department officials each had a "user identity", which made it easy to trace who had issued documents.

"If we suspect that documents have been issued fraudulently, we check on which user ID issued such documents and we investigate."

Three of the officials were arrested at the department's Vereeniging offices, two at Vanderbijlpark and one at Everton, he said.