Bristol scored three second-half tries at Ashton Gate to beat Stade Francais with a bonus point win which tightens their grip on Challenge Cup Pool Four.
Luke Morahan's try and the boot of Ian Madigan helped give the hosts a narrow half-time lead, with winger Lester Etien replying for the Paris club.
But Pat Lam's side took full control after the break as hooker Thacker drove over before Charles Pituau scored too.
Toby Fricker's try with the last play of the game sealed maximum points.
More to follow.
Bristol Bears: Piutau; Morahan, O'Conor, Bedlow, Leiua; Madigan, Randall; Woolmore, Thacker, Afoa, Attwood, Vui, Luatua, Jake Heenan, Hughes.
Replacements: Capon, Lay, Thomas, Holmes, Hamilton, Stirzaker, Lloyd, Fricker.
Stade Francais: Lapegue; Naivalu, Mapoe, Arrate, Etien; Segonds, Hall; Mavinga, Da Silva, Melikidze, Pyle, De Giovanni, Chapuis, Kordi, Godener.
Replacements: Latu, Camara, Tagi, Gabrillagues, Azagoh, Daguin, Danty, Tui.
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