BJP workers tried to barge into the office of the superintendent of police in Nalgonda to unfurl the flag but were arrested. A similar futile attempt was made in Warangal.
BJP state president G. Kishan Reddy, who hoisted the national flag after garlanding the statue of Sardar Patel near the assembly, said once Telangana becomes a separate state, the "liberation day" would be celebrated officially.
He said the Congress was not celebrating the day under pressure from the Majlis-e-Ittehadul Muslimeen (MIM).
The BJP has long been demanding official celebrations. Successive state governments have turned down the demand on the ground that this could create communal trouble in view of reservations from the Muslim community.
Muslim groups are opposed to any celebration as they claim that lives and properties of Muslims were targeted during "Operation Polo".