A police official said they completed the questioning in four days, although the court had remanded the MIM leader to their custody for five days.
The police had arrested the MIM leader Jan 8 and the next day a Nirmal court sent him to judicial custody for 14 days for the hate speech he delivered at a public meeting in Nirmal town Dec 22.
Akbar, a member of the Andhra Pradesh assembly from Chandrayangutta constituency in the old city of Hyderabad, is facing charges of sedition, waging war against nation and criminal conspiracy.
The court will later take up the hearing on a petition filed by police, seeking its permission to take Akbar's voice sample as he reportedly denied during questioning that the voice in the compact discs shown to him was his.
The voice sample is likely to be sent to a forensic laboratory in Chandigarh for audio and video authentication.
In another development, the MIM leader's lawyers filed a bail petition in the Adilabad sessions court. The petition is yet to be listed for hearing.