Consider the following reaction :

$3{\mathrm{Br}}_2+6{\mathrm{CO}}_3^{2-}+3{\mathrm{H}}_2\mathrm{O}⟶5{\mathrm{Br}}^{-}+{\mathrm{BrO}}_3^{-}+6{\mathrm{HCO}}_3^{-}$

Which of the following statements is true regarding this reaction?

In the following reaction the oxidation state of bromine on the reactant side is zero when it changes to ${\mathrm{BrO}}_3^{-}$ it gets oxidized by gaining oxygen and its oxidation state changes to +5 which indicates oxidation by losing 5 electrons. In $5{\mathrm{Br}}^{-}$ the oxidation state of bromine is  -1, indicating reduction by gaining 1 electron. Hence bromine is both reduced and oxidized.