A fire at a New York apartment building that killed three boys may have been started by candles after the electricity was cut off, city authorities have said.

Officials say the blaze started in a second-floor apartment at a six-storey building just blocks from Yankee Stadium in the Bronx.

Five-year-old Elijah Artis, two-year-old Jeremiah Artis and four-month-old Michael Turner were pronounced dead at a hospital.

Police say their 25-year-old mother and her two other children, a, four-year-old girl and girl aged just four months, are stable.