Health Minister Fahrettin Koca said the fire broke out in a private hospital and that it is believed to have started after an oxygen ventilator exploded.
Other patients receiving treatment were transferred to nearby hospitals, Koca said.
The Anadolu news agency said the fire took place at the Sanko University Hospital in Gaziantep. It cited a hospital statement identifying the victims as being between 56 and 85 years old.
Anadolu Agency reported officials from the provincial governor’s office said 19 patients were in the unit when a “high-pressure oxygen device” exploded at 4.45 am.