(DES MOINES, Iowa) -- A man tried to lure four elementary school students into his van by telling them he had puppies inside, the Des Moines Register reports.

The four Eddyville Elementary boys were out at recess, when the van, described as white with a gold stripe, pulled up on the other side of the fence next to the school grounds.

The man asked the students if they wanted to come see the puppies he had in his van, but the students did not enter the van, and the man drove off without exiting.

The school district sent a letter home to parents alerting them to the situation, and telling them that more security precautions are being implemented.

Sherriff’s officials from Mahaska and Wapello counties are investigating the case.

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