Iran’s judiciary said it had made arrests in the shootdown of a Ukrainian passenger plane that killed 176 people.

Judiciary spokesman Gholamhossein Esmaili said Tuesday “extensive investigations have taken place and some individuals are arrested,” according to the Associated Press.

Iran, which initially denied that one of its missiles had brought down the jetliner, did not disclose the number of arrests. On Saturday, Iran admitted that its Islamic Revolutionary Guard Corps had shot down the plane by mistake as it awaited possible confrontation with the United States after Iran fired a dozen missiles at military bases in Iraq housing American troops.

The missile was fired due to “human error,” causing the “horrific crash,” Iranian President Hassan Rouhani said Saturday. Rouhani called for a special court to be set up to investigate the matter.

“The judiciary should form a special court with a ranking judge and dozens of experts,” he said in a speech Tuesday. “This is not an ordinary case. The entire world will be watching this court.”

He added that the “responsibility falls on more than just one person,” and those found at fault “should be punished.”

The announcement of the arrests followed days of protests, with demonstrators criticizing the government’s attempt to cover-up its role in the downing of the plane.

The plane, en route to Kyiv from Tehran, was carrying 167 passengers and nine crew members when it was hit.