Mexico City: Egyptian forces bombed a convoy of Mexican tourists about five times in three hours, even after security forces on the ground had stopped them twice and cleared their passage, one of six survivors of Sunday's deadly attack says.

Susana Calderon is recovering from the bombing in a hospital in Cairo. Her husband, Luis, was among eight Mexicans killed in what has been described as an accident that claimed 12 lives.

"We were bombed some five times, always from the air," she told Mexican newspaper El Universal from her hospital bed. Her arm is marked with wounds and her right leg is paralysed, though doctors believe she will recover movement.

President Enrique Pena Nieto has demanded Egypt investigate the attack and assign blame. The Egyptian prosecutor general's office has announced a gag order on all news related to the investigation until its conclusion.