Can someone help me to identify this stinging insect?

Question

We call them timberflies here, but I don't think it's the proper name. I think it could be a type of wasp. Well anyway, my friend was stung by one on his knee and it swolled up for like a month. It has a dart or arrow-shaped stinger on the back and lives primarily in woodland areas. They are often seen with their stingers buried in trees.

Answer 1

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