Egyptian authorities suspended hot air ballooning over the ancient city of Luxor after two tourists were slightly injured during a ride early on Monday. According to a statement from the Ministry of Civil Aviation, a hot air balloon with 28 tourists drifted off course but eventually landed. The two injured tourists were taken to hospital for treatment.

The statement did not say how the injuries occurred or elaborate on the nationalities of the tourists. It said only that the balloon was at an altitude of 60 meters (197 feet) when it veered off course.

The ministry said ballooning would not resume until an investigation to determine the cause of Monday’s incident is completed.

Footage shared online purportedly from the incident shows a balloon landing slowly in an open area. Rescuers are then seen helping the tourists get out. A man’s voice is heard shouting for an ambulance.

Hot air ballooning over Luxor, 510 kilometers (320 miles) south of Cairo, is popular as it offers tourists spectacular views of ancient temples.

However, ballooning accidents are not uncommon. A hot air balloon crash near Luxor in 2013 killed 19 tourists, likely the deadliest such accident on record.

In 2009, 16 tourists were injured when their balloon struck a cellphone transmission tower. A year earlier, seven tourists were injured in a similar incident.