There are no reports of deaths in the blast so far. Most of the injured are believed to be foreigners.
There were 25 South African tourists on the bus, Egypt's state television reported. A security source said that at least five South Africans were among the injured.
"The five were slightly injured by shards of the broken glass of the bus," the source told DPA news agency.
One witness told Reuters news agency that he heard a "very loud explosion" near the site of the blast.
The Grand Egyptian Museum remains under construction and is expected to open next year. The blast caused no damage to the museum, the Antiquities Ministry said in a statement.
A blow to tourism industryIt is the second violent incident targeting tourists in Egypt in six months. In December 2018, at least two people were killed and 12 others wounded when a roadside bomb hit a tourist bus near the same pyramids.
The attack comes as Egypt's tourism industry is finally showing signs of recovery after years of turmoil that followed a 2011 uprising against former leader Hosni Mubarak.
No group claimed responsibility for the blast, but Islamic militants, who are active in Egypt's Sinai Peninsula, have in the past targeted minority Christians and foreign tourists on the mainland.
shs/sms (AP, Reuters)
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