Authorities say they have defused several pipe bombs at a park in Omaha.

The Omaha Police Department says the pipe bombs were discovered Thursday morning near a creek at Dundee-Memorial Park. A bomb response team was called in to help render the devices safe. Two of the bombs were found inside one bomb.

Officer Michael Pecha says the second bomb was found after authorities defused the first bomb. The third bomb was found the same way.

Pecha says it’s unclear how dangerous the bombs’ impact could have been.