An explosion shattered windows late Sunday at a housing complex used by foreign companies in Yemen's capital, but no one was hurt, security officials said.

The blast went off on the south side of San'a in an upscale neighborhood that houses Western diplomats, including Americans, said three security officials on condition of anonymity because they were not authorized to talk to media.

One of the officials who described himself as the head of security in the area said the blast was caused by multiple "projectiles." He would not give his name nor elaborate.

"Broken windows...were all that resulted from the projectiles' attack," the official said. No one was injured, he added.

A witness said the blast shook the neighborhood of Haddah.

"I heard a big blast that shook the southern suburb, but there was no fire or smoke coming out of the area," said Mohammed Omar, 30, who lives in the same area.

Police immediately cordoned off the area.

The officials said the housing compound is used by foreign companies of different nationalities and that the larger area includes diplomats' homes.

Last month, mortar shells were fired at the U.S. Embassy in San'a but exploded instead at a nearby girls' school, killing a security guard and wounding more than a dozen students.

After Sunday's blast, dozens of Yemeni troops in military jeeps lined the main road leading to the U.S. and British embassies on the eastern side of San'a.

Yemen, the poorest country in the Arab world, is Osama bin Laden's ancestral homeland and has a persistent al-Qaida movement that has attacked and killed foreigners on several occasions.

Separately, two Yemenis were killed and eight others wounded Sunday in continued clashes between security forces and protesters in the country's south.

Fighting has raged there for several days between authorities and thousands of former southern Yemen army officers, political activists and unemployed men who accuse the Yemeni government in the north of unequal treatment.