Iran’s judiciary said Tuesday that arrests have been made for the accidental shootdown of a Ukrainian passenger plane that killed all 176 people on board just after takeoff from Tehran last week.

The announcement came amid an upswell of anger and protests by Iranians in recent days over the downing of the jetliner last Wednesday and apparent attempts by senior officials in Iran to cover-up the cause of the crash, as reported by The Associated Press.

Iran, which initially dismissed allegations that a missile had brought down the plane, acknowledged only on Saturday — three days after and in the face of mounting evidence — that its Revolutionary Guard had shot down the plane by mistake.

Judiciary spokesman Gholamhossein Esmaili was quoted by Iranian state media saying that “extensive investigations have taken place and some individuals are arrested.” He did not say how many individuals had been detained or name them.

Iran’s president on Tuesday also called for a special court to be set up to probe the incident. “The judiciary should form a special court with a ranking judge and dozens of experts,” President Hassan Rouhani said in a speech televised in Iran. “This is not an ordinary case. The entire world will be watching this court.”

Rouhani called the incident “a painful and unforgivable” mistake and promised that his administration would pursue the case “by all means.” “The responsibility falls on more than just one person,” he said, adding that those found culpable “should be punished.” “There are others, too, and I want that this issue is expressed honestly,” he said, without elaborating.