Iran is planning to hold a massive funeral ceremony for the late President Ebrahim Raisi and others in the capital Tehran on Wednesday. Key political figures from other countries are expected to attend.

Raisi died on Sunday in a helicopter crash that killed all eight people aboard including Foreign Minister Hossein Amir Abdollahian.

A series of funeral events began on Tuesday. A procession took place in the holy Shiite Muslim city of Qom, central Iran. Crowds filling the main street payed their respects.

Local media say key government officials from neighboring Iraq and Turkey will attend the ceremony in the capital on Wednesday.

Russia says its parliament's Lower House Speaker Vyacheslav Volodin will lead the country's delegation to the ceremony. Russia and Iran have been strengthening their relations as both countries have a confrontation with the West.

The Iranian government also fears that Raisi's death could trigger criticism of the government. Raisi had a reputation, at home and abroad, for human rights abuse with his harsh repression of anti-government protests as president.

Following the accident, critical messages have been posted on social media along with tributes to Raisi. The Iranian Student's News Agency reported on Monday that the head of the prosecutor's office had instructed prosecutors to crack down on acts of spreading fake or insulting information online.