LEWISTON, Maine — The bullet that killed an Alaskan woman in 1993 could have been fired by a pistol owned by Auburn resident Steven Downs — and possibly a million other guns — according to testimony heard Tuesday.

Two firearms experts testified via videoconference in a Fairbanks, Alaska, courtroom in the rape and murder against Downs, 46, who had been a student at the University of Alaska Fairbanks at the time of the brutal crime.