A full investigation has been launched into the cause of a gas leak at the Grangemouth petrochemical site.
Eight fire appliances attended the refinery and police officers were sent to the site shortly after 12:00.
Refinery owners Ineos said there were no casualties as a result of the incident.
Ineos said a leak was detected on a pipe carrying ethylene gas in its Kinneil Gas manufacturing plant which was being isolated.
Police Scotland said the ongoing incident had now been resolved and Wholeflats Road had re-opened.
The company earlier said in a statement: "Staff were evacuated from the immediate area and our well-practiced emergency procedures were implemented with the incident management team being mobilised."
It said measures had been put in place to contain the leak in the immediate vicinity of the affected plant and road closures had been put in place as a precaution.
"All of the people working in the area have been accounted for and there were no injuries," the statement said.
"Other areas within the Grangemouth complex, including the adjacent refinery, were unaffected by the incident.
"A full investigation into the cause of the incident is under way.
"The regulators have been kept fully informed throughout."
Pupils at primary and secondary schools in Grangemouth were kept indoors over lunchtime as a precaution at the request of the police, a Falkirk Council spokesman said.
A spokesman for Scottish Fire and Rescue Service said: "At 12.12 on Tuesday, 2 May the Scottish Fire and Rescue Service was alerted to reports of a gas leak at the Grangemouth petrochemical site."
Supt Brian Auld, from Police Scotland, said: "I'd like to thank again the local community, employees and all involved in the emergency response for their patience, support and professionalism while emergency services and industry personnel worked together to manage this incident.
"I can give an assurance that disruption to the local road network was minimised and only necessary to ensure the safety of all, however, I recognise that the local community were concerned by the circumstances of this incident and the time taken to achieve resolution.
"Can I reassure all members of the community that the actions of first responders and Ineos staff reduced the potential for escalation and worked tirelessly to reduce the impact to the public".