Flaring at the Mossmorran gas plant in Fife has turned the skies to the north of Edinburgh red and orange, with some saying it is the most intense event they have seen so far.
Flames from the ExxonMobil Fife Ethylene Plant could be seen from ten miles away, leaving skies above Fife looking like "Mordor."
Many have been sharing dramatic pictures of the flaring on social media. They were visible as far as 10 miles away.
The plant receives hydrocarbons extracted from the North Sea, using a process called flaring to remove harmful gases.
The repeated use of flaring has angered people living nearby and provoked the ire of environmental watchdogs.
It's understood the latest flaring is part of a process to restart the plant.
Local councillor Darren Watt tweeted: "I passed Mossmorran main gate 30 mins ago & the flaring was the most intense I've ever seen.
"Although we've been assured by @exxonmobil_fep& @ScottishEPA that the restart is progressing well & as safely as possible, I'm sure we all want this to end at the earliest opportunity."
Another Twitter user said: "Mossmorran from at Johns park Rosyth. Welcome to mordor."
Campaigner Caroline Rance wrote: "Flaring from Mossmorran petrochemical plant can be seen for miles around. Just imagine what it's like to live nearby - the noise, light & air pollution."
In a statement the Scottish Environment Protection Agency (Sepa) said: "Sepa is aware of fluctuations in the elevated flare at Mossmorran as part of the final stage of the facility restart and specialist officers continue to monitor.
"We're working hard to address the root-causes of 'unacceptable flaring' making flaring an exception rather than routine."
