On Friday, bomb threats were received at nine Nebraska courthouses in the southeast corner of the state.
In each case, a male caller said there was an explosive device in the courthouse.
The calls were made between 11:06-11:36 a.m. to courthouses in Cass, Gage, Jefferson, Johnson, Lancaster, Otoe, Richardson, Saline and Seward counties, Nebraska State Patrol spokeswoman Deb Collins said.
The first call came into Otoe County, with the last call to Lancaster County, Collins said.
The buildings were cleared, but no credible evidence was found at any of the courthouses.
Collins asks anyone with information that might aid in the investigation into the source to contact their local law enforcement agency.