LINCOLN, Neb. (AP) — Officials from two Nebraska counties say allowing people to text emergency calls has some challenges, even though it has expanded emergency services and saved some lives.

Buffalo and Douglas counties began their text-to-911 services in January 2015. Officials say calling 911 is still the fastest, most effective way to assure first responders can get to the scene.

Interim Douglas County 911 Director Mark Conrey says text exchanges in Omaha are processed more slowly than regular 911 calls and that location information transmitted with the messages can be unreliable.

But in Buffalo County, the system helped two Kearney children, who successfully alerted authorities via text that their dad was drunk and driving them to Colorado in April. Buffalo County Sheriff Neil Miller says they’ve only had problems receiving photos from some carriers.