The United Nations says emergency workers in Algeria have rescued two of its staff members who were believed to have died in Tuesday's twin bombings in Algiers.

A U.N. spokeswoman on Wednesday confirmed that two U.N. employees were pulled alive from the rubble, but a number of U.N. staff members remain missing. She said nine are confirmed dead.

Algeria's Interior Ministry says a total of 31 people were killed in the truck bomb explosions outside U.N. offices and a government building.

U.N. Secretary General Ban Ki-moon has instructed top aides to review the organization's security procedures. In a statement, issued in Bali, Indonesia, where he is visiting, Mr. Ban strongly condemned the attack, saying words cannot express his "sense of shock, outrage and anger."

Al-Qaida's North African wing has claimed responsibility for the blasts.

At least 100 people were injured. Officials say the death toll could rise as the search continues inside the wrecked buildings.

The offices of the U.N. Development Program and the U.N. High Commissioner for Refugees were damaged by the blasts.

French President Nicolas Sarkozy and other European leaders have condemned the bombings.

The White House called the blasts a case of "senseless violence" and said they were carried out by "enemies of humanity who attacked the innocent." The U.S. State Department says the United States stands with the government of Algeria, and is ready to provide assistance.

Algerian militants linked to al-Qaida have carried out a series of attacks in the country this year, including suicide bombings that killed 33 people in Algiers in April.

Algerian Islamists rose up against the government in 1992 when it scrapped elections that an Islamic party was poised to win.

Some information for this report was provided by AFP, AP and Reuters.