Screenshot via Google Maps
Nederland is about 45 miles northwest of Denver.
Police said that the bomb was active, but failed to detonate.
A police officer found the object, which authorities identify as an improvised explosive device (IED), on Tuesday morning outside of the Nederland Police Department and Boulder County Sheriff's Office substation.
A nearby shopping center was evacuated as the Boulder County Regional Bomb Squad and bomb technicians from the FBI investigated the device.
The FBI took the lead in the investigation Wednesday and is working to find the suspect who placed the bomb, FBI Denver spokesperson Deborah Sherman said.
"We are trying to determine who did this and why. Right now everything is a possibility," Sherman said.
Officials are asking anyone with information to contact the FBI Denver division at (303) 629-7171.