The publishers of Jacques Pauw's hit exposé "The President's Keepers" believe a power outage during the book's launch at Hyde Park on Wednesday evening is "too much of a coincidence".
NB Publishers CEO Eloise Wessels said the launch had progressed substantially before the power outage occurred.
"It seemed like too much of a coincidence in view of the threats to the author and publishers of the book," Wessels said.
"The launch had progressed quite far by the time that the power outage occurred. When attempts to restore the power supply failed, the 1,000 people that attended queued very politely for almost two hours to have their books signed by the author by the light of cellphones. It was an incredible experience."
The book reveals several scandals involving President Jacob Zuma and his associates and is the country's fastest-selling book in history.
City Power is expected to comment on the outage, and questions have been issued to Hyde Park Corner.
This is a developing story.