WASHINGTON – A police investigation found no evidence that fires on three D.C. ambulances this summer were deliberately set.

The Washington Post reports the findings are largely in line with what fire investigators previously said: that the fires — two of which happened on the same day — likely were accidents caused by a variety of mechanical issues, such as a fuel leak and electrical problems.

The exact causes for the fires were not determined, according to the Post.

Although no one was injured in the ambulance fires, they created more problems for a department already struggling with its fleet.

Over the summer, ambulances broke down — one ran out of gas on the way to a call at the White House — and a lack of working units slowed response times.

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