A team of Egyptian security forces reportedly shot dead 12 people, who were part of a Mexican tourist convoy on a desert safari, while chasing some armed Islamic State (Isis) terrorists.
Two of the deceased were Mexicans and 10 were Egyptians, while 10 other tourists were injured in the firing.
A joint task force comprising Egyptian police and military were chasing the Isis men in the country's vast western desert bordering Libya, when the counter-terror unit came across the tourists' convoy.
Mistaking the four tourist vehicles to be that of terrorists, the security forces opened fire, the Egyptian interior ministry said in a statement, according to Reuters.
The incident sparked an uproar in Mexico. President Enrique Pena Nieto condemned the attack and demanded an "exhaustive investigation".
"Mexico condemns these deeds against our citizens and has demanded an exhaustive investigation of what has occurred," Nieto posted on his offiicial Twitter account.
According to BBC, Egypt has now set up a special investigative team to probe the incident. The report citing local sources said that the tourists were fired upon from an Apache helicopter.
However, Egypt has claimed that the tourists had "illegally" entered the zone as it was a prohibited area, The Guardian reported.
Hours after the incident on Sunday (13 September), the Isis in Egypt released a statement on Twitter that it has successfully managed to repel an attack by the Egyptian military.