Lili Reinhart's dog has undergone surgery after being attacked while they were out on a walk.

The 23-year-old actress has revealed via Instagram Stories that her beloved pet pooch Milo - who was rescued from Furever Freed Dog Rescue in British Columbia in Canada - suffered a ''pretty deep wound'' on his neck during the vicious attack.

Lili - who was visibly emotional in her video message - said: ''This is weird for me and I'm not exactly sure why I'm doing it, but I guess for all the people out that that care about my little dog Milo.

''I was taking him out today to get some exercise. I had a mask and gloves on so don't start with me about that. He was attacked by another dog.

''It was pretty bad. I had to rush him to the hospital, and he's there now getting surgery.''

Meanwhile, Lili previously confessed she feels ''intimidated'' by the ''physique'' of her 'Riverdale' co-stars.

The actress has been left feeling ''very insecure'' at times about her on-screen appearance - but she has ultimately grown to accept that she has ''bigger boobs'' and ''cellulite''.

Responding to a fan question about body image, Lili admitted on Twitter: ''Actually, not everyone on this show is perfectly chiselled.

''And even I feel intimidated by the physique of my surrounding cast mates sometimes when I have to do bra/underwear scenes. I've felt very insecure due to the expectation that people have for women on tv, what they should look like.

''But I have come to terms with my body and that I'm not the kind of person you would see walking on a runway during fashion week. I have bigger boobs, I have cellulite on my thighs/butt, and my stomach sticks out rather than curves in. (sic)''