On Wednesday, a Ukrainian Boeing 737 passenger plane crashed near Tehran, killing all 176 people onboard.

Iran's armed forces on Saturday admitted that the Ukrainian plane was "unintentionally" hit by Iran and "human error" was to blame.

The Ukrainian plane "was mistaken for a hostile target" near an Iranian "sensitive military site of Islamic Revolution Guards Corps (IRGC)" on Wednesday amid rising threats by the United States, a statement by the Iranian armed forces published by the official IRNA news agency read.

The incident was due to "human error," the statement was cited as saying.

Iranian Supreme Leader Ayatollah Ali Khamenei on Saturday urged relevant authorities to conduct investigations over "possible shortcomings" leading to the recent crash of Ukrainian plane over Iran's airspace.