One of the flags of ULFA, which along with five other northeast groups had called for their customary boycott of Independence Day celebrations and a general shut down, was found on a post in the market area of Shila village, 10 km from Barpeta town, police said.
Another flag was found flying in the compound of local Damodar Sarma school.
Locals informed police who took the flags away around 9 am.