The first plane carrying bodies of Iranian pilgrims killed in last week's hajj stampede in Saudi Arabia arrived Saturday in Tehran.
President Hassan Rouhani was among several senior officials at the Tehran airport for the arrival of the plane carrying the bodies of 104 of the 464 Iranians killed in the stampede.
Iran has blamed the stampede on mismanagement by Saudi Arabia, and Iranians have staged several protests outside the Saudi Embassy in Tehran.
"It should become clear whether some individuals were guilty in this incident or not. If it is proven that some officers were culpable, under no circumstances will we let the blood of our loved ones go in vain,'' Rouhani said.
Iran's Supreme Leader Ayatollah Ali Khamenei had warned that Saudi Arabia would face "harsh" measures if its regional rival did not send the bodies of Iranian pilgrims back home.
Iranians made up, by far, the largest share of the 769 people killed in the September 24 disaster. Saudi Arabia has launched an investigation into the stampede and said officials would be held accountable if it found that mistakes were made.
There have been multiple deadly stampedes during the hajj, but the one this year was by far the worst since 1990, when more than 1,400 people died.
The hajj pilgrimage is one of the five pillars of Islam, and all able-bodied Muslims are required to undertake it once in their lives.
Some information for this report was provided by AP, AFP