Residents who live on Red Rock Road and Brushy Plain Road have been affected by a power outage Thursday night.
Branford Police said they received multiple calls from residents who say they heard a loud boom.
According to Connecticut Light and Power, 1,814 customers are without power because of a transformer fire that pulled down some power lines.
There is no estimate on when power will be restored.
CL& P crews are working to fix the problem.