Story highlights A U.S. official says the death also highlights the extent of Iranian involvement in Syria

Iran has become increasingly public about its aid to Syria's government

Washington (CNN) The death of a top Iranian military commander in Syria this week has dealt a "psychological blow" to elements backing Syrian President Bashar al-Assad, according to a U.S. intelligence official.

The killing of a commander in the Revolutionary Guards Corps at the hands of ISIS also highlights the extent of Iranian involvement in Syria and the dire straits in which Assad finds himself, Washington-based analysts say.

Brig. Gen. Hossein Hamedani was killed outside Aleppo, Syria, where he was advising the Syrian army in its fight against extremists, Iranian state media reported Friday.

Iranian media carried messages of condolence from Iranian President Hassan Rouhani, who described Hamedani's death as a big loss and applauded the senior commander for his bravery.

"He was in charge of [Iranian] operations inside Syria," said former CIA officer Reuel Marc Gerecht. "He's been involved in this from A to Z, so in the short term, it's probably a fairly significant loss."

Read More