WASECA, Minn. (AP) -

Police in southern Minnesota say melting snow has revealed three small handmade explosives on the playground of an elementary school.

A KSTP-TV report on Saturday says Waseca police were called this week to Hartley Elementary School.

Police say the devices appeared to have been there for a while. One was found already detonated inside a toy. A bomb squad detonated a second one and a third failed to ignite.

No one was hurt.

Police say it's not immediately clear whether the devices were intentionally left on the playground to hurt kids. They ask anyone with information to call 507-835-9720.