The deal with Zhuzhou Electric Locomotive company, a subsidiary of CSR Corporation Ltd , is part of a 300 billion rand ($32.5 billion) upgrade to Transnet's railways and ports to overcome freight bottlenecks in Africa's largest economy.
A spokeswoman for the Public Protector, an independent, state-appointed anti-corruption body, said the deal was under investigation but offered no details.
A complaint was lodged in December by a Cape Town-based Marxist party, which compared the Transnet contract with a similar Chinese train tender in neighboring Namibia that also drew the attention of graft-busters.
In the complaint, the Workers International Vanguard Party said trains supplied by CSR to Namibia in 2005 were so fault-prone they were withdrawn from active service soon after delivery.
"Transnet management must have been well aware of this history. This raises the question as to how did it come about that the tender was still awarded to them," party secretary Shaheed Mahomed said.
Officials at Transnet said they would respond as soon as possible. (Reuters)
