A bomb exploded early Friday morning in Microsoft's South African office in Johannesburg, shattering windows but causing no injuries.
None of the four security guards who were on the property at the time of the blast were injured, said Mark Hill, general manager of Microsoft's South African office.
The office park in the upmarket suburb of Sunninghill in northern Johannesburg provides marketing and customer support in Southern Africa and the Indian Ocean region.
"Weâ€™re very pleased that none of our employees were injured and weâ€™re cooperating with the local authorities as they investigate the explosion," local Microsoft spokesman John Pinette told NorthWest Cable News Friday morning.
South African police said the blast was caused by a bomb detonated in the courtyard of the u-shaped Microsoft building. The device blew out windows but caused no structural damage to the building.
"It's difficult to understand who would do this," said Hill. "We had not received any threats before this."
Investigators are piecing together the evidence to try to find out who is responsible.
The office's 170 employees were asked to work from home Friday. Hill said the office should be fully operational by Monday.