Activists have blocked Grangemouth oil plant
Extinction Rebellion campaigners are preventing access to the Ineos petrochemical plant and have blocked two roads with boats.
The group said protesters had also locked themselves together.
They accused the petrochemical manufacturer of being Scotland's biggest climate change polluter.
Protesters are also demonstrating outside the company's London headquarters.
An Extinction Rebellion statement said it had blocked the Bo'ness Road gate with a boat and had another boat at the Ineos office on Inchyra Road.
Extinction Rebellion Scotland said Covid-19 safety precautions are being taken, including face masks, social distancing and use of hand sanitiser, while participating activists are using a track and trace app.
Campaigners held up banners stating "No Future in Fossil Fuels" and "Climate Justice = Social Justice".
Annie Lane, 26, a campaigner from Glasgow, said: ""We are here to expose the climate destruction that Ineos is causing. We are running out of time, with the climate crisis affecting so many in the global south already."
A Police Scotland spokesman said: "Officers are currently in attendance at a peaceful protest in Bo'ness Road and Inchyra Road, Grangemouth.
"The roads are blocked and drivers are asked to avoid the area. We are liaising with the protest organisers, Extinction Rebellion."