Image source, PAImage caption, Soldiers at the garrison in an undated file photograph
Firefighters expect to work all night as a fire blazes at the military barracks accommodation block in Catterick Garrison, North Yorkshire.
North Yorkshire Fire and Rescue Service said in a statement that multiple crews were at the scene, along with an appliance from County Durham and Darlington.
"The incident is expected to be ongoing throughout the night," the statement said.
Unverified videos and images shared online show flames and smoke rising up from a building as bystanders watch.
The BBC has asked the Ministry of Defence for comment.
Hipswell and Colburn councillor Kevin Foster told local media that details were limited at this stage.
"My immediate concern is for the safety and wellbeing of everyone at the camp, including our military personnel, their families and the emergency services responding to the incident," he said.
This is a developing story.
