Fire marshals say the causes of the three separate fires Friday at Montefiore Medical Center and NYC Health + Hospitals North Central Bronx Campus were all accidental.

They say the fires were caused by a carelessly discarded cigarette, a car engine issue and an electrical problem dealing with an oil-filtering pump.

 Officials say one fire occurred at the Montefiore Moses Campus and the other two were on the NYC Health + Hospitals North Central Bronx Campus.

MORE: FDNY: 3 fires break out at Montefiore Medical Center

No injuries were reported. The fires were put out quickly.

The hospital did not have to be evacuated so patients inside were not disrupted.