Md Idris Ali, office secretary of Chattogram Metropolitan unit BNP, confirmed the news.
City unit BNP convener Shahadat Hossain and member secretary Abul Hashem Bakkar, among others, secured the bail.
On January 16, a clash broke out between the BNP supporters and police when a BNP rally was going on in front of the party office in the Kazir Dewri area.
At least 30 people from both the BNP and police were injured in the clashes while law enforcers detained 20 people.
Police sued some 200 BNP men in four cases on that night.