SANAA, Yemen - Yemen's president has apologized to President Barack Obama for the attack on the U.S. Embassy in Sanaa, the Yemeni capital, by a mob angry over an anti-Islam film.

The U.S. Embassy in Yemen says nobody was harmed in Thursday's assault. "All embassy personnel are safe and accounted for," spokesman Lou Fintor said.

President Abed Rabbo Mansour Hadi also ordered an investigation into the attack. Several hundred protesters stormed the embassy's compound, brought down the U.S. flag in the courtyard, burned it and replaced it with a black, Islamist banner.

Hadi avowed to bring the culprits to justice, saying the attack by a "rowdy crowd" was part of a conspiracy to derail Yemen's close relations with Washington.