Authorities say five people, including three young children, have been killed in an apartment house fire in New Jersey's largest city that started in a vacant building next door.

Newark fire officials say those killed lived in two third-floor apartments.

The fire started just before 2 a.m. Friday and spread quickly, damaging four other buildings and displacing about 15 people. The cause remains under investigation.

Newark Fire Capt. John Brown says a 3-year-old girl and her 4-year-old brother died in a back apartment. He says their parents escaped the blaze with two other children, and were hospitalized with non-life threatening injuries.

Fire officials say another young female child, a teenage boy and an adult died in the other apartment.

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