Fire broke out in apartment in outskirts of Bologna.

Italian authorities have opened an investigation into a fire that caused the deaths of three children and their mother in the northern city of Bologna on Thursday night.

The deceased children included two-year-old twins and a six-year-old, according to Italian media reports.

Their mother, reportedly a 32-year-old Romanian woman, died while being taken to hospital.

The fire, which broke out in a fourth-floor apartment on Via Bertocchi in the outskirts of Bologna, may have been caused by an electric heater, Corriere della Sera reports.

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