Story highlights The ambassador was not in the building

The blast was from a car bomb

A large explosion outside the residence of the Iranian ambassador to Yemen killed six people and wounded 12 others in Sanaa on Wednesday.

The newly-appointed Iranian ambassador, Hasan Nam Wadi, was not in the building at the time, but it's not clear if his family was, two interior ministry officials said.

All Iranian diplomatic personnel were safe and accounted for, the Tasnim news agency in Iran reported.

The car bomb went off near the entrance of the diplomatic residence, officials said.

Photos provided to CNN from the scene showed at least two large holes blown in the side of the residence with security forces and others walking over piles of concrete rubble outside.

Among those killed were a guard at the residence, and a woman and her child who were walking by.

No group immediately claimed responsibility for the attack, though it has the hallmarks of al Qaeda, officials said.

"We expect al Qaeda to claim responsibility for the attack since they vowed to target and kill Houthis and their allies," a senior Interior Ministry official told CNN.

Houthis are followers of a sect of Shia Islam. Iran is predominantly Shiite.

The newly appointed ambassador arrived in Yemen just days ago and has strong links with the Houthis.

Al Qaeda -- the Sunni Muslim terrorist network -- has for months threatened to kill Houthis after Houthi fighters defeated Sunni tribes in several provinces.