A flight test of the Bulava ballistic missile that was conducted at 19:50 MSK (15:50 UTC) on September 7, 2006 apparently ended in failure. According to a representative of the Ministry of Defense, quoted by ITAR-TASS, the missile strayed off course and fell into the sea. The missile was launched from underwater from the Dmitry Donskoy submarine of the Northern Fleet, deployed in the White Sea.
This is the first failed flight test of the missile. The first two flight tests - on September 27, 2005 and December 21, 2005 - were successful. (The very first test, on September 23, 2004, was a pop-up test that did not involve firing of missile engines. UPDATE 09/08/06: One more pop-up test, on December 11, 2003, involved only a mock-up of the missile.)
UPDATE 09/14/06: The cause of the failure was a malfunction of the first stage of the missile at the time of ignition.