Iran claims it has arrested the person who recorded the footage showing a Ukrainian passenger plane being shot down by a missile.
The person being detained is believed to face charges relating to national security, according to a media source.
Flight PS752 was brought down on Wednesday last week after it took off from Tehran killing all the 176 people on board.
Iran has said it was accidentally shot down and has announced the arrest of several people over the incident. President Hassan Rouhani said a “special court” would oversee his country’s investigation.
“This will not be a regular and usual case. The whole world will be watching this court,” he said in a speech.
Mr Rouhani also stressed that not one person should be blamed for the “tragic event.”
“It’s not only the person who pulled the trigger, but also others who are responsible,” he said.
Iran initially denied that the plane was hit by a missile, but later admitted that its air defense systems hit the passenger jet.
When the video was shared on social media, viewers were led to say it was showing a missile hitting the aircraft.
Iranian media reported Iran’s elite Revolutionary Guards had taken into custody a person who posted a missile video last week striking the plane. But a London-based Iranian journalist who initially posted the footage insisted his source is free, and the Iranian authorities have detained the wrong person.