The U.S. has reopened its embassy and other offices in South Africa, three days after closing them because of a security threat.

U.S. Embassy spokeswoman Sharon Hudson-Dean said the embassy in Pretoria and other facilities were open for business Friday.

U.S. officials have not given any details about the threat that prompted them to close the embassy, three consulates, and U.S. aid offices on Tuesday.

However, a South African newspaper said the United States took action following a threat from an al-Qaida splinter group.

In a Thursday report, The Pretoria News said the splinter group telephoned the embassy Monday and apparently gave detailed information about possible attacks against several U.S. government buildings in South Africa.  

The newspaper says its information is from "well-placed security sources."  It cites an intelligence source as saying the call to the embassy is believed to have come from South Africa.

Some information for this report was provided by AFP.