TEHRAN (Iran News) – Iran’s President Hassan Rouhani said Tuesday that all those responsible for the accidental downing and crash of the civilian Ukrainian plane last week must be punished.

“For our people it is very important in this incident that anyone who was at fault or negligent at any level” face justice, said Rouhani in a televised speech, adding that the “tragic event” would be thoroughly investigated.

He described the fatal incident “a painful and unforgivable” mistake and promised that his government would pursue the case “by all means.”

“More than just one person is responsible for the Ukrainian plane crash,” said the president, adding that those found culpable “should be punished.”

“There are others, too, and I want this issue to be expressed honestly,” he said, without elaborating.

Rouhani also called for a special court to probe the tragic incident.

“The Judiciary must form a special court with a high-ranking judge and dozens of experts…This is not an ordinary case. The entire world will be watching this court.”

Arrests in airliner case

Meanwhile, Judiciary spokesman Gholamhossein Esmaili said: “extensive investigations have taken place and some individuals are arrested.” He did not say how many individuals had been detained or named.

The Ukraine International Airlines plane crashed after it was “unintentionally” targeted by Iranian air defense shortly after takeoff from Tehran last Wednesday, killing all passengers and crew on board.

On Saturday, Iran’s military said that the jetliner was brought down due to “human error”.

The plane, en route to the Ukrainian capital of Kyiv, was carrying 176 passengers and nine crew members from several countries, including 82 Iranians, 57 Canadians — including many Iranians with dual citizenship — and 11 Ukrainians, according to officials.

The plane was downed at a time when Iran’s Armed Forces were on heightened alert after launching a volley of missiles at Iraqi bases housing US troops.

Iran fired the missiles in retaliation for the US assassination of Lt. Gen. Qassem Soleimani, the head of the Quds Force of the Islamic Revolution Guards Corps (IRGC) on January 3.

Addressing that issue on Tuesday, Rouhani said while “the root of all sorrows goes back to America… this cannot be a reason for us not to look into all the root causes” of the air disaster.