The bodies of two suspects were found near Kibler Park in Johannesburg after the latest attempt to steal fuel from a Transnet's pipeline, the parastatal reported on Monday.
One body was found in a shack located some 30 metres away from Transnet's petroleum pipeline and the other was found in a tunnel burrowed between the shack and the pipeline.
"It is suspected that they were overcome by fumes while trying to siphon petrol from the pipeline on Saturday night. The structure and tunnel were demolished [on Sunday]," Transnet Pipelines said in a statement.
"The incident over the weekend is a harsh reminder to perpetrators that tampering with the petroleum pipelines and associated infrastructure can lead to disastrous consequences, including personal injuries and fatalities, extensive environmental damage and fire."
Transnet has had 90 fuel theft incidents in the current financial year.
Together with its specialised tactical teams, inclusive of aerial and ground support, Transnet made 68 arrests, including that of two kingpins.
"The perpetrators will face the full might of the law as tampering with the pipeline, or colluding to tamper, is a Schedule 5 offence in terms of the Criminal Matters Amendment Act … and all perpetrators are charged accordingly," Transnet Pipelines said.
The parastatal urged all petroleum retailers and members of the public to refrain from buying fuel from unregistered traders, to curb the demand for illegal petroleum products and to join in the fight against petroleum theft.