A minor explosion at an electricity sub-station in Stubbins left homes without power.
The explosion caused a fire which damaged the sub-station in Rosebank, Stubbins at about 8.25am on Sunday.
The incident led to power being cut to 23 nearby homes, Electricity North West said.
Fire crews from Ramsbottom and Rawtenstall stations were at the incident for an hour, and they found there had been a technical fault at the sub-station, during an adjustment in the voltage output.
Power was restored to the affected homes just before 6pm on Sunday.
An Electricity North West spokesperson said: “We apologise to those affected by this fault, and thank the fire service for their assistance.
“Our engineers quickly arrived on-site and worked to remove the damaged equipment and restore power.
“Thankfully these types of faults are rare, and we are carrying out a full investigation into the cause.”