What appear to be crude stone tools may provide evidence that people lived in Minnesota 13,000 to 15,000 years ago, which if confirmed would make them among the oldest human artifacts ever found in North America, archaeologists said Friday.

Archaeologists in the northern Minnesota town of Walker dug up the items, which appear to be beveled scrapers, choppers, a crude knife and several flakes that could have been used for cutting, said Colleen Wells, field director for the Leech Lake Heritage Sites Program.

"They don't look like much," Wells acknowledged. "They don't look pretty."