The fire, which broke out in a car garage on the ground floor, spread to the upper floors, trapping the residents.
The incident occurred in the six-storeyed building at around 9.35 a.m. in the Bazar Ghat area in Nampally.
Four fire tenders rushed to the scene and doused the fire, while rescue and relief operation is currently underway.
Three injured people were shifted to hospital.
Deputy Commissioner of Police Venkateshwarlu told media persons that preliminary investigation showed that six persons died of suffocation as the smoke engulfed the upper floors.
He said the fire started from a car which was being repaired in the garage on the ground floor.
“Within few seconds, the fire spread to the upper floors. Few families living on second, third and fourth floors were trapped,” he said.
Local residents said the presence of chemicals in the garage led to rapid spread of fire.
IANS
