Around 15,000 homes and businesses were left without power in west Dublin after an ESB substation burst into flames.
Emergency services were alerted to the blaze - at Kylemore Way, in Bluebell - at around 7.25pm yesterday.
Massive flames and thick black smoke billowed into the air as units from Dublin Fire Brigade (DFB) and gardai arrived at the scene.
Luckily, there was no one injured in the incident. However, emergency services had to move people away from the fire - for fear of a huge explosion.
A large number of gardai maintained a cordon of around 500 metres around the site, while shoppers at a nearby Lidl supermarket were advised to move away from the area.
The road was closed off as response teams battled the dangerous blaze.
The fire also caused some traffic disruption as the AA warned of reduced visibility on the roads around the ESB compound.
At one point, the garda air support unit was called in to help monitor the situation.
Units from DFB, which had arrived from Tallaght, Dolphin's Barn and Tara Street, continued to monitor and battle the blaze late last night.
A housing estate is located near the scene, across the Grand Canal.
A spokesman for the ESB said that it was believed that a transformer had caught fire, which in turn set the compound ablaze.
"The incident happened at a 220kv substation which has left areas of west Dublin with power outages," he told the Herald.
The worst affected areas were Lucan, Tallaght and Inchicore, where homes and businesses were left without light for up to an hour.
"Repair teams were dispatched immediately. While they await DFB to extinguish the fire, we can get people back [with electricity] fairly quickly," the ESB spokesperson said.
He added that power could be drawn from alternative sources while the necessary work was under way at the substation.
The smoke from the fire was so extensive that it could be seen widely across the city.
In a statement, emergency services warned the public to stay away from the fumes and urged people to remain indoors and keep their doors and windows shut.
"Members of the public are advised to avoid the fumes emanating from this fire," the statement said.
Meanwhile, there was also reports of smoke coming from the Trinity Boat Club on Infirmary Road last night. However, is understood that the incident was minor.