South Africa's criminal intelligence chief, Lt-Gen Dumisani Khumalo, has been arrested and has appeared in court on allegations of fraud and corruption.

Gen Khumalo was picked up on Thursday evening after landing at the main international airport in Johannesburg by members of the anti-corruption unit, local media reported.

He made his court appearance in the capital, Pretoria, on Friday, alongside six co-accused, all senior police officers.

Their lawyer said they intended to plead not guilty to any charges laid against them.

Details of the charges are not yet clear but local media say Gen Khumalo and the other six had been linked to an ongoing investigation into alleged abuse of intelligence funds and potentially unlawful appointments within the South African Police Service (SAPS).

It marks the second wave of arrests within two weeks targeting the SAPS' Crime Intelligence unit.

Three other top officials are facing corruption and other charges.

The arrests have raised questions about the integrity of the unit, which is meant to be actively preventing crime and cracking down on criminals.

The Democratic Alliance, the second-biggest party in the coalition government, welcomed the arrests, saying it was a right "step in rescuing an organisation on the brink of collapse".

"This points to yet another serious breach of trust within a critical state institution tasked with performing our nation's policing functions and mandate," the party said in a statement.

The Economic Freedom Fighters party said the arrest of Gen Khumalo was not an isolated scandal, but the "latest symptom of a sick, and hollowed-out policing system, which urgently requires structural overhaul".

Gen Khumalo became the head of the Crime Intelligence unit in 2022.

Up until then, he had served in different police units for more than two decades.

Numerous corruption cases against senior police officers over the years have tainted their reputation in the country.