A Krunichev Proton-M/Briz-M rocket suffered a launch failure on Feb 28, 2006.
The Briz-M stage is rumoured to have shut down 27 minutes 31s into a
planned 31-minute second burn, according to several sources.
This was a very long engine burn, but the AMC-15 launch in 2004 saw
a 37.5 minute burn, so it's not a record for Briz-M. (second 30-minutes burn of the Briz ended prematurely)
There are now two objects cataloged in a 505 x 14695 km x 51.5 deg
orbit, presumably the Arabsat 4A payload and Briz. Since the failure was
before the end of the second burn, the Briz DTB tank will not have
separated, and the B object is Briz with the DTB still attached.
The accidental explosion on Feb 19, 2007 of
the Arabsat-4 Briz upper stage 2006-06B, stranded in orbit in 2006 with
tonnes of propellant left on board, is thought to have generated
hundreds more debris objects, none of which have yet been cataloged.
After evaluating a lunar fly-by maneuvre to
rescue the satellite, Arabsat 4A was commanded to re-enter the Earth atmosphere on Mar 24, 2006 over the
pacific.The satellite probably fired its apogee engine around 00:20 UTC to lower its
perigee into the atmosphere; according to an MSNBC press report it
reentered over the South Pacific at 02:07 UTC.