What happen when metal is exposed surrounded by a microwave oven ? the lid popped of my soup can, can this damage my oven?

the lid popped of my soup can, can this damage my oven?
Do you know why burner on my Kenmore...
Answers:    I heated something minus realizing the markedly edge of the metallic peel-off lid hadn't come next to the rest. It was perchance 1/16 of an inch wide and a couple inches long.

When I heated the container contained by the microwave, it arced--a mini-lightning bolt--and smoked.

After letting it cool completely, we cautiously tried the microwave, which seem to work just fine. That be at least ten years ago.
Termites swarming.?
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