Police have ruled out a crush and say the party-goers may have ingested a toxic substance.

Most of the dead were teenagers. Some are reported to have been celebrating the end of their exams.

Local officials said they feared it was a case of under-age drinking gone wrong.

President Cyril Ramaphosa expressed his condolences, and said he was concerned that young people had gathered at a venue that should be off-limits to under-18s.