Assurances have been issued by an environmental agency after “intense flaring” at a chemical plant in Fife sparked alarm.

The “flames” from ExxonMobil’s Mossmorran plant near Cowdenbeath could be seen for miles on Thursday night, with many taking to social media to express fears.

One Twitter user in Edinburgh described the flare “as bright as streetlights” despite being 12 miles away.

The restart of the plant is in its final stage, with the Scottish Environment Protection Agency (Sepa) previously issuing a warning about elevated flaring, which “may fluctuate in size”.

Cowdenbeath councillor Darren Watt tweeted that “the flaring was the most intense I’ve ever seen”.

He also told the PA news agency: “The ‘fire’ is the flame from the elevated stack at ExxonMobil’s plant in Cowdenbeath.

“Although it’s pretty intense and a worrying sight, it’s not a fire.”

In a statement on Thursday, 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.

“The short and medium-term investment we’re requiring the operators to make, from noise reducing flare tips in 2020 and 2021 and planning, designing then delivering new ground flare capacity will make a real difference to local communities.”