At least 16 people were injured in a blast targeting a bus near Egypt's Giza pyramids Sunday, security sources said.
Officials said the bus was carrying 28 people, most of them South African tourists. Videos circulating online show the bus windows blown out or shattered.
Egyptian Tourism Minister Rania Al Mashat tweeted: "Of the 28 passengers on the bus we can confirm some minor injuries with three being treated at the hospital as a precaution."
There was no immediate claim of responsibility for the blast.
South African Ambassador Vusi Mavimbela and his team in Egypt are visiting victims in hospitals, officials said.
The explosion took place near the Grand Egyptian Museum, which is undergoing construction, near the Giza pyramids. A statement issued by the antiquities ministry said the explosion caused no damage to the museum.
In December, three Vietnamese tourists and one Egyptian guide were killed when a bomb hit their bus near the Giza pyramids.