(Associated Press) A Utah art teacher was fired amid complaints that images of classical paintings containing nudity were passed out in a classroom and seen by sixth-graders, a newspaper reported.

Mateo Rueda said he wasn’t aware that a set of educational postcards from the elementary school library contained a few works depicting nudity when he handed them out during a lesson, the Herald Journal newspaper said Thursday.

He removed the cards when they made students uncomfortable, the paper reported .

“This is not material at all that I would use. I had no idea,” Rueda said.

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