Authorities say a large fire is burning in a mixed-use building in northern New Jersey, but no injuries have been reported.

It was not immediately known what caused the fire, which broke out around 3:30 p.m. Monday along Bergenline Avenue in Union City, one of the most densely populated areas of the city in Hudson County.

The four-story building contains several apartments and has businesses on the ground floor. Fire officials say the building was quickly evacuated.

Fire officials say the blaze apparently started on the fourth floor. Flames and thick, black smoke were pouring out of the building as firefighters entered the building, but they were later forced out due to the fire's intensity.

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