GIZA, Egypt- A bus carrying 14 Vietnam tourists hit a bomb that was hidden beside a wall on Marioutiya Street.

Egypt’s interior ministry said that the device was likely hidden near a wall on Giza street, in the outskirts of Cairo.

According to Prime Minister Mostafa Madbouly, the bus hit the device after taking a route that was not planned without notifying the security forces. He also added that two people were critically wounded.

The roadside bomb killed at least four people including an Egyptian guide and three Vietnamese tourists. Mostafa told a local TV that the injured had been taken to the nearby Al Haram hospital.

He went ahead to say that they have been in contact with the Vietnam embassy in order to contain the impact of the incident. Dozens of military, police, and firefighters were seen at the site where the explosion occurred.

Although no immediate claim of responsibility has been reported, Islamist militants who are linked to Isis have targeted foreign visitors in the past. This explosion marks the first deadly attack on foreign tourists in Egypt for over a year.

The bus driver later said that he had followed the standard tourist bus route.