Last week, a report from veteran U.S. television journalist Dan Rather described Chavez's health situation as "dire, " citing an unidentified source's assessment that the Venezuelan president may not see the final results of the October elections due to the progression of his cancer.

CNN: Venezuela's Chavez appears chipper, energetic on state TV

Reid's unsubstantiated claim, based on an unidentified source, was intended to keep alive the push by Democrats to force Romney to release more of his past tax returns than the two years disclosed so far -- his 2010 filing and an estimate for 2011.

CNN: Presidential campaign gets even dirtier

Novak said the special prosecutor already had waivers from all three of his sources - that is Mr. Rove, Mr. Harlow, and this third primary and unidentified source - to testify before the grand jury that was trying to figure out whether to indict people on this stuff.

NPR: Novak Reveals Details of CIA Identity Leak

According to the Reuters news agency, which quoted an unidentified government source, Germany is very close to lifting its growth forecasts.

BBC: NEWS | Business | French and German growth picks up

The APS news agency quoted an unidentified security source for the new death toll and said the fatalities include both Algerian and foreign workers.

NPR: Algeria: 12 Hostages Have Died In The Siege

In that case, hackers gained access to source code under development for an unidentified future product.

CNN: Microsoft servers hit by another hacker