FWIW there was a public opinion poll by Levada back in 2002 about this. 6% said FSB did it, 37% said that there's no clear evidence but they could have done it,

FWIW there was a public opinion poll by Levada back in 2002 about this. 6% said FSB did it, 37% said that there's no clear evidence but they could have done it, and 38% said that it's definitely not the feds.