DERBY, Kan. (KAKE) - Federal law enforcement is investigating what the City of Derby is calling a “computer network disruption.” 

City Manager Kiel Mangus said IT staff discovered the problem on Saturday, Jan. 14. The city’s email network is down. 

“They’re evaluating our system to see, you know, what occurred, how it occurred, you know, when can we get things back,” Mangus said. 

The FBI is investigating the disruption, along with third-party computer specialists. Mangus said this is causing delays in utility bill payments in Derby. 

“We’re not charging late fees,” he said. “Also, the ones that go out will go out a little bit later, we'll adjust the due dates accordingly.”

The City cannot send out utility bills to residents who receive them online. Elaine Baker gets hers in the mail and said she received it before the system outage. 

“You never know if your WiFi's going to go down or, you know, if…yeah, I just like to get the paper thing,” Baker said. 

Baker came to City Hall to drop off her payment Wednesday. She said she had heard about the network disruption. 

“Making sure you can easily reach out and get information out to the public sometimes is difficult when you have technology down,” Mangus said. 

City leaders are asking residents to call City Hall or email [email protected], the City’s backup g-mail account if they need help. People can also come to City Hall in person. 

“We’re outperforming our services, public works, police, fire, everything's operating,” Mangus said. So, mostly on their side of things, we're continuing to operate as usual, just with some limitations.”

Mangus said he does not know how long this will last. 

“You quickly realize, when you have, you know, nearly 250 staff members, the way you communicate and go about things and how much you use that technology in day-to-day operations,” he said.