Apparently there has been an explosion in a K-223 strategic nuclear submarine from the Russian Pacific Fleet, killing one crewmember.
From: Xinhuanet: Sailor killed in blast in Russian nuclear
submarine
A Russian sailor was killed in an explosion in a strategic nuclear submarine of the Russian Pacific Fleet, the Itar-Tass news agency reported on
Friday.
Spokesman for the Russian Navy Igor Dygalo told Interfax on Friday evening "the explosion occurred when the pressure pipeline linked to a fresh
water tank burst" on Nov. 14.
The incident took place on board of a K-223 strategic missile cruiser -- a submarine of the second generation.

Related news sources:
Interfax: Sailor killed in blast in Russian nuclear submarine on Nov 14
Yahoo! News - Report Russian Submarine Blast
Kills 1
Guardian: Russian Submarine Blast Kills 1
From: Yahoo! News - Report Russian
Submarine Blast Kills 1
the accident occurred last Sunday while the submarine was docked at the Vilyuchinsk base in the far eastern Kamchatka Peninsula.
The accident damaged one section of the submarine but the vessel has remained fully operable
According to Russian Web resources, the K-223 is a Delta-III-class submarine built in 1980. It is equipped to carry 16 intercontinental ballistic
missiles.
Two other crewmen were injured

I´ll update when/if I find more information about this...
[Edited on 2004/11/19 by Hellmutt]