Egyptian security forces mistakenly killed 12 people in a tourist convoy in the country's western desert, the Interior Ministry said Monday.
The security forces were pursuing terrorists there when they accidentally hit four SUVs carrying Mexican tourists and Egyptians who were in a banned area, the ministry said. Ten other people were also injured.
Mexican Foreign Secretary Claudia Ruiz Massieu confirmed that two of those killed were Mexican citizens and officials were working to confirm the identities of other possible victims.
Mexican President Enrique Peña Nieto condemned the attacks, saying on Twitter that he was asking the Egyptian government to "perform an exhaustive investigation" into the killings.
To assist victims and their relatives, Peña Nieto said he was increasing the number of diplomatic personnel in Egypt.
"I am profoundly sorry that fellow citizens have lost their lives," he tweeted.
Egyptian officials claim the safari convoy had wandered into a restricted area.
The tour company involved "did not have permits and did not inform authorities," Rasha Azazi, a spokeswoman for the Egyptian Ministry of Tourism, told The Associated Press, adding that any trips to that area are required to be cleared by officials.
"They were not supposed to be there," she said, but could not provide further information on the circumstances of the shooting.
Egypt's western desert is popular among safari enthusiasts, but has not been known as a hotbed of militant or insurgent activity. Police and military there have primarily been concerned with combatting smuggling along Egypt's large and porous border with Libya.