At least 40 Indians are among 49 people killed in a fire at a residential building in the Kuwaiti city of Mangaf, India's foreign ministry has said.

The fire broke out on Wednesday in a building where dozens of workers stayed.

Video shared on social media showed flames engulfing the lower part of the building and thick black smoke billowing from the upper floors.

Authorities said many of the casualties are from the southern Indian states of Kerala and Tamil Nadu. Around 50 Indians have also been injured.

Filipino and Nepali workers are also among the injured.

Two-thirds of the Kuwaiti population is made up of foreign workers and the country is highly dependent on migrant labour, especially in the construction and domestic sectors.

Human rights groups have regularly raised concerns over their living conditions.

Local media reports said the building housed 196 workers and there are suggestions that it may have been overcrowded.

A senior police officer told state TV that there were a "large number" of people in the building at the time of the fire.

"Dozens were rescued, but unfortunately there were many deaths as a result of inhaling smoke from the fire," he said, adding that warnings were often issued about overcrowding in this type of accommodation.

Kuwaiti Deputy Prime Minister Sheikh Fahad Yusuf al-Sabah accused property owners of greed and said violations of building standards had led to the tragedy.

"Unfortunately the greed of the property owners is what led to this," Sheikh al-Sabah, who is also acting interior minister, told Reuters news agency.

"They violate regulations and this is the result of the violations," he said.

Interior Ministry spokesman Maj-Gen Eid al-Oweihan told state TV that the fire was reported at 06:00 local time (03:00 GMT) on Wednesday. It was later brought under control.

Indian Prime Minister Narendra Modi has sent his condolences to the victims and their families.

"The fire mishap in Kuwait City is saddening," he said on X.

"My thoughts are with all those who have lost their near and dear ones. I pray that the injured recover at the earliest."

He said the Indian embassy was monitoring the situation and working with the authorities on the ground.

Kirti Vardhan Singh, a junior minister in the government who left for Kuwait on Thursday morning, said DNA tests were being carried out to identify the victims.

"An Air Force plane is on the ready. As soon as the bodies are identified, the kin will be informed and our Air Force plane will bring the bodies back," he told news news agency ANI.

An eyewitness, Manikandan from the Indian state of Tamil Nadu, told BBC Tamil that many of the workers had been on night shifts.

"Some of those who returned to that apartment early in the morning were cooking food after coming back from work," he said.

"Once the fire erupted, it spread rapidly. People living in the building were not able to control the fire."