Emma Roberts -- Signs of Combat After Arrest

A bruised and bandaged Emma Roberts was spotted one week after her domestic violence arrest -- and based on the pics ... it seems the fight was worse than we thought.

TMZ broke the story -- Emma was taken into custody in Montreal on July 7 after an altercation with boyfriend -- and fellow "American Horror Story" co-star -- Evan Peters.

Montreal law enforcement sources tell us a 3rd party phoned police about an alleged fight in the couple's hotel room -- and when cops arrived -- they found Evan with a bloody nose and a bite mark. Sources close to Emma deny Emma bit Evan.

But in these photos, shot in Beverly Hills on July 14, it looks like Emma didn't exactly emerge unscathed herself -- she has some nasty scars on her knee, black and blue thighs, and a bandage on her left elbow.

Emma was booked into a Montreal jail -- and released the next morning when Evan refused to press charges.