MEXICO demanded an investigation yesterday after two of its citizens were among 12 people killed when Egyptian troops fired on tourists in the Sinai desert.

Egyptian officials said the safari group did not have permission to be in the area, and that troops mistook them for terrorists.

But they have not offered a full account of Sunday’s incident, in which another 10 people were wounded.

The Interior Ministry said in a statement that a joint military-police force was pursuing “terrorist elements” in the area when it fired on four cars that turned out to be carrying tourists.

Egyptian Tourism Ministry spokeswoman Rasha Azazi said the tour company involved “did not have permits and did not inform authorities.”

Mexico’s President Enrique Pena Nieto condemned the attack and demanded a full investigation.

The country’s Foreign Ministry confirmed that at least two of the dead were Mexican nationals and said victims were still being identified.

Foreign Secretary Claudia Ruiz Massieu said Mexicans wounded in the attack told their ambassador they were fired upon by helicopters and aircraft.

Ms Ruiz Massieu has also demanded an investigation, as well as the support of Egyptian authorities for Mexican nationals being transported to Cairo.

Mona el-Bakri, spokeswoman for Dar al-Fouad hospital where the wounded were being treated, said two of the seven Mexicans being treated also hold US citizenship.

US embassy spokesman Brian Shott said officials were looking into whether a US citizen was involved in the incident.