Ten people, including five children, were killed in a fire that broke out Friday morning at an apartment building in Vaune-Velaine, near the French city of Lyon, according to preliminary reports by Reuters.

Local authorities said the cause of the fire is unknown at this stage. There were 170 firefighters working at the scene.

The fire broke out early Friday morning in a seven-story apartment building in Vaux-en-Velin. A cordon is in place at the scene of the fire.