Defence lawyers on Thursday completed cross examinations of Federal Investigation Agency technical officers during a hearing of the Usman Mirza sexual assault case at an Islamabad sessions court.

Mirza and his accomplices were indicted for sexual harrassment, torture and blackmail after a video that showed the accused and his accomplices threatening the victims at an apartment in Sector E-11 of the federal capital went viral.

Mirza, the prime accused, was indicted in September along with six others, namely Hafiz Attaur Rehman, Idras Qayyum Butt, Rehan, Umar Bilal Marwar, Muhib Bangash and Farhan Shaheen, who were involved in filming the objectionable video of the young couple.

On Thursday's hearing Mirza and five other accused were presented in the court of Judge Atta Rabbani.

During the hearing, FIA official Masood Ali told the court he didn't have original video of the incident, but he got a downloaded version from the internet.

At this the defendant's lawyer asked Ali to show him proof of whether he had done any specialist course in audio or video.

Responding to the lawyer, Ali said he had done a course from Australia which included forensics of audio and video.

Then, the lawyer asked the FIA official which unit did Google belong to; Ali wasn't able to respond.

During his cross examination, FIA technical officer Anees ur Rahman told the court he was doing investigation on a Twitter trend on which "immoral" videos were uploaded. However, his investigation did not include the number of real and fake accounts which had posted the videos.

Later, the court adjourned the hearing of the case till December 7.