Law enforcement officials are still trying to explain how a supposedly peaceful interview with an important witness in the Boston bombing case turned into a deadly shooting, but as usual, every new attempt to explain the death of Ibragim Todashev only raises more troubling questions. After originally accusing the suspect (and potential murderous accomplice of Boston bomber Tamleran Tsarnaev) of attacking an FBI agent with a knife, and then walking back that claim entirely, an new anonymous source says Todashev may have injured the agent with a table and a metal pole. Or maybe not.

Here's the way the attack was described in The New York TimesEveryone seems to agree that after several hours of interrogation, Todashev was prepared to confess to an unsolved murder that he and Tamerlan Tsarnaev were connected to. Then things get a lot less clear:

At that moment, Mr. Todashev picked up the table and threw it at the agent, knocking him to the ground. While trying to stand up, the agent, who suffered a wound to his face from the table that required stitches, drew his gun and saw Mr. Todashev running at him with a metal pole, according to the official, adding that it might have been a broomstick.

So not only has the story changed again, it has now changed twice in the same sentence. The weapon has now gone from nothing to a knife, back to nothing to a table to a metal pole to a broomstick. Todashev was also apparently shot more than once, after an initial volley of "several shots" somehow failed to bring him down.

Oh, and there's a pretty big difference between a metal pole and a broomstick, and the fact that the Times source can't decide which one it is suggests they don't really know happened either. (CNN reported that Todashev owned a samurai sword that was in the room, but no one has yet suggested that he wielded that at any time.) With at least three witnesses, you're likely to get three different stories and we might never know which, if any of them, is the most accurate.

The new version of events also doesn't answer the question of why the FBI agent immediately began firing his weapon or why the other police officers in the room failed to intervene. Which leaves us right back where we started: A confusing scene, an apparently unnecessary death, and a very suspicious explanation. And on top of all that, the FBI lost what could have been one of their most valuable sources of information on what the Tsarnaev brothers were really up to before they carried out their attack.

UPDATE: John Miller of CBS News has a few extra details this morning that add to the Times account. According to his sources, one of the Massachusetts state troopers in the room became concerned that Todashev might try something, but rather that speak up and provoke him, he sent a text to the FBI agent. When the agent looked down to read the text, that's when Todashev attacked, again with an unknown object. The other officers in the room never pulled their guns.

Miller (who is a former FBI agent himself) also says an FBI shooting review board will investigate the shooting.