Two car bombs ripped through downtown Algiers apparently targeting  a United Nations building and Algeria's Constitutional Court:

U.N. Secretary-General Ban Ki-moon has condemned the blasts which he described as "terrorist attacks". Jean Fabre, spokesman for the U.N. Development Program, told CNN a search was underway for the 12 missing staffers.

Ron Redmond, spokesman for the United Nations High Commissioner for Refugees headquarters in Geneva, Switzerland told CNN staff were missing from the main U.N. building in Algiers.

One explosion occurred outside the constitutional court in the Algiers neighborhood of Ben Aknoun while the other took place in the residential area of Hydra tearing the front off the U.N.'s headquarters in the city.

A reporter from CNN affiliate BFM quoted hospital sources as saying 62 people were killed in both blasts. Redmond said the U.N. headquarters and a separate building housing its refugee agency's office had "suffered extensive damage."

"Apparently this was an extremely powerful bomb," Redmond told CNN. "It's caused a lot of damage and right now we're just trying to sort out where our staff are."