The incident occurred shortly after 6pm on Tuesday at the Earlsgate Roundabout in Grangemouth.
It came a week after Chief Constable Phil Gormley told the public there would be more armed officers on the streets in the wake of the Manchester bombing. However, police said this was a planned operation and it is understood not to be terrorist related.
Uniformed, plain clothes and armed officers were all involved in Tuesday’s action which saw a man detained.
A knife was also spotted being placed in an evidence bag.
A Police Scotland spokeswoman said: “Police Scotland firearms officers, supporting a planned operation, detained a man from a vehicle at the Earl’s Gate Roundabout in Grangemouth.
“This was part of an ongoing investigation and at no time were the public at any risk. A 45-year-old man has now been charged in connection with a breach of the peace and a report will be submitted to the Procurator Fiscal.”