INEOS has apologised to residents in Grangemouth after an episode of "unplanned flaring" last night
Petrochemical Plant bosses have also started an investigation as what cause the short-term event.
Residents reported hearing what they have described as booming noises from around 9pm.
The sky is also said to have turned a bright orange colour.
Taking to social media one person said: "I am guessing this flaring wasn't planned, as I didn't see any warnings about it online like usual.
Another wrote: "What a noise that INEOS is making tonight, I am Polmont and can hear it. It's like boom noises that keep coming and going.
A third commented: "Aye cheers INEOS, it's half 10 and I'm up for ma work at 2am. It's about time they were dished out big fines for this. Happening far too often."
A spokesperson for INEOS said: "We are investigating the circumstances around a short term unplanned flaring episode last night (22 March) at the INEOS Grangemouth site.
"We apologise for any inconvenience this may have caused our local community."
