The police in South Africa are looking into claims that Andre de Ruyter, the departing CEO of state-owned power company Eskom, was poisoned.

A day after he submitted his resignation, Mr De Ruyter claimed someone poisoned his coffee with cyanide.

Mr De Ruyter has drawn criticism for his failure to end the pervasive business corruption that led to the worst blackouts in South Africa’s history.

The story first surfaced over the weekend when Mr De Ruyter told EE Business Intelligence editor and energy analyst Chris Yelland that after consuming the coffee, he felt weak, dizzy, and confused and began vomiting.

However, poorly managed Eskom said due to the police investigation, it could not comment on Mr De Ruyter’s claim that someone tried to poison him at his Johannesburg office on December 13.

Pravin Gordhan, South Africa’s minister of public enterprises, asserted that a thorough investigation would be conducted into the alleged attempt on Mr De Ruyter’s life, promising that those responsible would face charges.

The head of communications for Solidarity, a union at Eskom with 6,000 members, Morne Malan, stated that Mr De Ruyter’s fight against corruption was a factor in the alleged poisoning.

Mr De Ruyter is scheduled to leave Eskom on March 31. He officially assumed his position as CEO in January 2020.