At least two people were killed after a fire broke out on Wednesday in a five-story residential building on the outskirts of the Indian capital city of New Delhi, police said.

It is suspected that the blaze in the building was triggered by an electric scooter being charged in the ground-floor parking area in Sector 66 of Noida suburb.

Police rescued over 100 people from the building.

Officials said the flames quickly spread to nearby petrol-powered two-wheelers, while dense smoke rose through the staircase and corridors, leaving residents on the upper floors with no escape route.

Reports said the dense smoke, rather than the flames, posed the biggest challenge for the rescuers during the rescue operation as it spread rapidly through the building within minutes.

According to police, the fire services responded immediately and reached the spot along with seven fire tenders, hydraulic platforms and rescue vehicles. The building housed around 50 families.

Two occupants developed serious health complications after inhaling dense smoke and were shifted to the district hospital by ambulance, where they were declared dead, police said.

Police have registered a case against the building's leaseholder and operator under appropriate legal sections on charges of negligence and taken them into custody.

Meanwhile, the exact cause of the fire is being ascertained.

Chances of fire in India are often high as owners of the buildings and houses usually ignore safety standards vis-a-vis fire and store fuel and combustible materials in a haphazard manner.