BEIRUT: An Iranian official has been killed at the hands of “armed terrorist groups” while he was en route from the Syrian capital to Beirut, Iran’s embassy in Lebanon said late Wednesday, in a incident whose details remain sketchy.

“With great sorrow and regret, the Iranian Embassy announces the martyrdom of engineer Hussam Khoshnevis, who headed the Iranian Committee for Reconstruction in Lebanon, at the hands of armed terrorist groups while he was en route from Damascus to Beirut,” the mission said on its website.

The Syrian regime, a close ally of Iran, frequently refers to rebels seeking to topple President Bashar Assad as “armed terrorist gangs.”

Iran’s Revolutionary Guards said Thursday the head of the Iranian Committee for Reconstruction in Lebanon, whom it identified as Hassan Shateri, was killed at the hands of “Zionist [Israeli] regime mercenaries and backers.”

"Commander Hassan Shateri was martyred en route from Damascus to Beirut at the hands of Zionist [Israeli] regime mercenaries and backers," Gen. Ramezan Sherif, a Revolutionary Guards spokesman, said in a statement, reported Agence France Presse.

Both Iran and Syria claim the revolt against Assad is backed by regional and foreign powers.

Shateri’s funeral was held in Tehran Thursday morning, and was attended by Revolutionary Guards chief Ali Jaafari, head of the foreign operations Quds Force unit Qassem Soleimani and Ali Saidi, representative of Iran's supreme leader Ayatollah Ali Khamenei, according to AFP.

Iran’s Foreign Minister Ali Akbar Salehi condemned the attack, describing it as a “terrorist act.”

Salehi was quoted by Iranian media as saying he "valued the selfless services of this commander of Islam and his tireless efforts in the reconstruction of the damaged areas in the southern Lebanon,” AFP said.

The reason for the differing names and details of the killing remain unclear.

According to Iran's Fars news agency, Shateri was killed Tuesday, although it did not elaborate on the circumstances of his death, AFP reported.

The Syrian Observatory for Human Rights said Shateri was shot dead by rebels while he was en route from the Syrian capital to Lebanon.

"We do not know exactly where he was shot, but we do know that a rebel group ambushed his vehicle while en route from Damascus to Beirut," Britain-based Observatory director Rami Abdel Rahman told AFP.

A Syrian opposition commander, according to Reuters, said the attack was carried out by rebel fighters near the Syrian town of Zabadani close to the Lebanese border.

Lebanese security officials, who spoke on condition of anonymity, told the Associated Press there was no indication that the Iranian official was killed on Lebanese soil.

Lebanon’s As-Safir newspaper reported Thursday that information indicated that Khoshnevis had been in Syria, specifically in the northwestern city of Aleppo, on a reconstruction project.

Iranian Ambassador to Lebanon Ghazanfar Roknabadi linked Khoshnevis’ death to Israel, Iran’s long-time foe.

Roknabadi, who received condolences at a reception in Beirut, said Khoshnevis’ death proved that Israel was trying to intimidate all those who support the resistance in Lebanon.

“Engineer Hussam Khoshnevis was assassinated because he played a major role in Lebanon’s reconstruction following the Israeli aggression against the country in July 2006,” said Roknabadi.

"The martyr served the oppressed and supported the resistance and his assassination is a clear sign that the Zionist enemy does not accept his successful work,” he said.

“However, this will never stop us from keeping up our support to the resistance,” he added.

The Gathering of Muslim Scholars of Jabal Amel, in a statement, also slammed the killing of Khoshnevis, which it described as part of an Israeli-American plot.

“The gathering denounces this deadly assassination on Syrian soil that reflects the obvious grand Zio-American plots that Syria faces through severing all the help to the sons, people, resistance that render Syria strong,” the scholars said in a statement.

“The gathering ... mourns brother Hussam Khoshnevis, who was martyred in Syria at the hands of the criminal groups running amok,” the scholars said.

Khoshnevis was involved in numerous construction projects in south Lebanon, including the building of churches and mosques, the establishment public gardens, including one at the Fatima Gate along the border with Israel.

The official also supervised the construction and repair of bridges and roads across south Lebanon. –With Agencies