MESA, Ariz. - Fire crews found the bodies of a woman and a young boy in Tuesday evening’s apartment fire, according to the Mesa Police Department.

The relationship between the two was not immediately clear.

But the circumstances were suspicious, said Nik Rasheta, spokesperson for the department.

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Was is accidental or was it foul play?

“Those are the same questions that we have as well,” said Rasheta, “and we’re not quite ready to say whether it’s one way or another.”

What was particularly striking in this case was fire crews explaining the fire essentially put itself out.

A 911 caller described only seeing smoke coming from the apartment unit near Country Club Drive and Broadway Road.

The fire originated in a bedroom, which is where the two bodies were found.

Since foul play is still a possibility, detectives were not able to say what their cause of death was.

Family members of the victims were not present when first responders arrived.

Police were still working to speak with them and were could not immediately identify the two victims.