The force helicopter was involved earlier today, Friday, and has now been stood down, but uniformed officers are continuing with the search.
A Police Scotland spokesman said: “Police in Forth Valley Division are currently carrying out a search in Bo’ness to trace a male in connection with a serious assault that took place in Boyd Street, Laurieston, on Thursday, November 14.
“Local officers were assisted by the Air Support Unit after the male fled from police.”
Eyewitness, Davie Baxter, (65) who was driving in the town around 11am on Friday said: “I was driving along when I saw the police helicopter circling above the town. Then the next thing I knew I had police vehicles screaming past me with their lights and sirens on, so there’s obviously something big going on.”