The blaze in an Iraq COVID 19 hospital killed at least 23 and injured dozens following explosion of oxygen tanks.
Videos on social media show firefighters scrambling to extinguish the flames as people flee the building.
Iraq's Prime Minister Mustafa al-Kadhimi called for an immediate investigation into the causes of what he called a "tragic accident".
About "30 patients were in the intensive care unit", which was reserved for the most severe cases of Covid-19 in Baghdad, a hospital source told the AFP news agency.
The injured and patients who weren't hurt have been taken by ambulance to other hospitals nearby.
"The fire caused many of the oxygen tanks designated to support the COVID19 patients in the hospital to explode. Baghdad so far dozens of victims have been reported," Steven Nabil said on Twitter.