An air strike killed a commander from Iran’s Islamic Revolutionary Guard Corps at the Iraq-Syria border at some time between Saturday and Sunday, Iraqi security officials said on Monday.
They could not confirm the identity of the commander, who they said was killed alongside three men in the vehicle with him.
The vehicle was carrying weapons across the Iraqi border and was hit after it had entered Syrian territory, Iraqi security officials said.
Iran-backed Iraqi paramilitary groups helped to retrieve the bodies, the officials said.
Local military and militia sources confirmed the story.
The incident came days after Iranian nuclear scientist Mohsen Fakhrizadeh was assassinated in Tehran in a killing Iran has blamed on Israel.
Israel launched air raids against what it called a range of Syrian and Iranian targets in Syria last week.
It showed that it will pursue its policy of striking Iranian targets in the region as US President Donald Trump prepares to leave office.
Iraqi officials more fear conflict ahead of president-elect Joe Biden taking office because he is considered to be less confrontational with Iran.
Iran-backed Iraqi militias are still reeling from the US assassination of Iranian commander Qassem Suleimani in Baghdad in January, alongside their Iraqi leader, Abu Mahdi Al Muhandis.
They have vowed revenge against the US.