Dozens of people have died in a fire in a large factory in Delhi.

Fire engines streamed through the Indian capital to the blazing fire which had engulfed a five-storey building in the city’s old quarter early Sunday morning.

It is understood a large number (60 to 70) of factory workers and contracted laborers were asleep in the building at the time, and a large number of them perished in the fire.

Home Minister Amit Shah described the tragedy as a “tragic loss of precious lives.” The Hindustan Times put the death toll at the time of writing at 43.

“The fire was big and we pressed in more than 50 fire tenders. Till 9:30am we had shifted at least fifty-six people to hospital. All of them had fallen unconscious because of smoke. Our men got into the building and we pulled out occupants. They are in large number and were sleeping on different floors. Rescue operations are continuing and we are yet to figure out how many people were inside the building” Delhi Fire service director Atul Garg said Sunday.

Prime Minister Narendra Modi took to Twitter to express his sentiments. “The fire in Delhi’s Anaj Mandi on Rani Jhansi Road is extremely horrific. My thoughts are with those who lost their loved ones. Wishing the injured a quick recovery. Authorities are providing all possible assistance at the site of the tragedy,” he posted on Twitter.

Delhi firefighters were alerted to the fire at 5.22am local time on Sunday. Fifty-six people were evacuated, unconscious due to smoke inhalation, and were taken to local hospitals.