South African man allegedly poisoned three sons, fourth struggling for life.

Three brothers, Lehlogonolo, Katleho, and Tebogo Khoabane, died after eating a poisoned energy drink supplied to them by their father, according to South African police.

The three boys, ages 16, 13 and 6, perished in Heidelberg, Gauteng, on Thursday morning, May 26. A fourth sibling is in critical condition in the hospital, while a fifth refused to drink.

The father allegedly gave his five sons the poisoned drink, which four of them drank when they arrived at school, according to reports.

The man is also suspected of giving the same alcohol to a dog that died the next morning and then attempting suicide.

The lads were students at Ratanda Primary and Khanya Lesedi Secondary Schools in Ratanda, according to Gauteng MEC Panyaza Lesufi.

"Four of the aforementioned students drank the energy drink when they arrived at school on Thursday. 

Unfortunately, two of the students died soon after complaining of stomach aches, and one was transported to the local hospital but died on the way. 

"The fourth sibling is in severe condition in the hospital, while the fifth sibling, thankfully, did not swallow the energy drink," Lesufi said.

He expressed his heartfelt sympathies to the deceased pupils' family, particularly their mother.

"I also send my sympathies to the students' friends, other students, and teachers, particularly those who witnessed these awful circumstances," Lesufi continued.

He stated that the cause of the fatalities is unknown at this time, and that law enforcement agencies are examining the circumstances surrounding the deaths.

However, according to Johannes Khoabane, a family representative, the guy has apologised for poisoning his children.

After the attempted suicide, the father is recovering in hospital, according to Khoabane, who added that he is under police protection.

"The nurses who were helping us at the clinic claim he apologised," Khoabane said outside the family home in Ratanda on Friday. He has apologised, according to them. He claims he has no idea what he was doing."

Khoabane went on to say that the family was baffled as to why the guy would wish to murder his children.

"We don't know what happened. We're all curious about what happened. When we questioned his wife if they had fought, she responded no.

 I have no idea what happened. He is the only one who knows. We're trapped; he needs to explain why he did it," he continued.