The explosions, according to Iranian state media, took place at a ceremony commemorating Qassim Suleimani, the top commander killed by a U.S. drone strike four years ago.

A pair of explosions in Iran on Wednesday in the cemetery where Iran’s former top military general, Qassim Suleimani, is buried killed 73 people and wounded 171, according to Iranian officials, heightening tensions in the region even further a day after a drone strike killed several Hamas officials in a suburb of Beirut, Lebanon.

Iranian officials told state media that a pair of bombs placed in bags along the route of the cemetery had exploded as a procession of people was on its way to the cemetery to commemorate the four-year anniversary of Mr. Suleimani’s assassination by the United States. The officials said the explosion occurred after two bags filled with explosives detonated, apparently via remote control, leaving bodies in pieces on the ground.

The explosions in Kerman, Iran, came four years after an American drone strike assassinated General Suleimani, the longtime commander of the Iranian Revolutionary Guards Corps’ powerful Quds Force, at Baghdad airport.

General Suleimani had been hailed in Iran and in parts of the wider region as a hero for building a Tehran-led network of regional militias that countered the United States and Israel across the Middle East, and he continues to enjoy near-mythic status among pro-government Iranians.

That network included Hamas, the military and political group that controls Gaza, as well as Hezbollah, the armed political party that dominates much of Lebanon. Hezbollah has been clashing with Israeli forces on Lebanon’s southern border even as Hamas battles Israel in Gaza.

Hamas, Lebanese and American officials all blamed Israel for a strike on Tuesday in Lebanon, which killed a senior Hamas deputy and skilled tactician, Saleh al-Arouri. The identities of those who died in Iran on Wednesday were not yet known.