The Public Investment Corp.’s board of directors offered to resign amid an inquiry into allegations of wrongdoing.

The move throws the South African fund manager of more than 2 trillion rand ($150 billion) deeper into crisis.

The institution responsible for most South African government worker pension funds has been “destabilized” by a series of claims, including against at least four board members, Chairman Mondli Gungubele said in a letter to Finance Minister Tito Mboweni co-signed by eight other executives. “Our assessment is that this may not be the end,” they said, adding that they are prepared to stay on until a new board is appointed.

Africa’s largest fund manager is the subject of an ongoing inquiry into various investment decisions, including in the bonds of Eskom Holdings SOC Ltd. and technology company Ayo Technology Solutions Ltd. In the past year, half of the PIC’s executive committee have been suspended or resigned, including ex-Chief Executive Officer Daniel Matjila.

Last week, the PIC said it would investigate allegations against two non-executive directors and acting CEO Matshepo More, who was not one of the signatories on the resignation letter.

State of Paralysis

“These events have been unbearable to us as individuals and have undoubtedly had a negative impact on our professional integrity,” the board members said. They are “an attempt to bring the institution into a state of paralysis.”