A woman and her three children, including a one- month -old baby, were burnt to death in their house in Nkangbe, a suburb of Minna, the Niger state capital, The Nation reports.
The fire, which started at about 11.30 pm, raged for over three hours burning down the house completely.
However, the second wife identified as Fati and her two children were rescued with severe burns.
They are receiving treatment in an hospital, it was learnt.
Their husband, simply identified as Baba Abba, was said not to be home when the incident happened.
He was said to be working in Abuja, only returning home during the weekend.
The men of the fire service responded to the distress call immediately but the rescue was hampered by the jammed doors and window burglaries, making rescue very difficult.
The neighbours said they did not know the cause of the fire because the community had not had electricity for over two months as their transformer has been bad.
The cause of the fire remains unknown as even the fire service are working to find out the cause of the incident.
One of the neighbours, who engaged in the rescue, Musa Ibrahim, said they called the fire service immediately they saw flames coming from the house.
He said that they tried their best to rescue the women and the children but could not as the fire was very intense.
“We tried as much as we could but we couldn’t get inside. With the help of the fire service, we rescued the second wife through the window and she was wounded and had some burns.
“When we were able to get inside as men of the fire service tried their best to rescue the second wife and her children but before we could get inside, they were already burnt.”
One of the men of the fire service said: “There were four casualties and the cause of the fire is not known. The people here say their transformer has been spoilt and they said the people in the house did not put on the generator that night.
“Everything in the house was burnt down, nothing could be salvaged. It is very unfortunate. We are awaiting the arrival of our Controller to come and access the house.”
Another fire service officer said: “The door was locked and jammed. If the window burglary was not there, we would have rescued them on time. The burglary hampered our rescue.”