According to the BBC News, the bus was carrying Vietnamese tourists, as well as two Egyptians – a driver and a rep from the tourist company.
The bomb explosion is believed to have taken place on the Mariouteya Road, which is a popular street with tourists.
The Interior Ministry had told Sky News Arabia that the explosion was caused by an improvised bomb and that two of those injured were Egyptian.
In a statement the Interior Ministry said the ‘improvised explosive device was hidden next to a wall’, and that it detonated at around 6.15pm local time. An investigation into what happened has already begun.
Shocking images shared on social media show a bus with its windows blasted out and damage to the inside.
Police and medics attended the scene and those injured have been rushed to hospital.