Is this a rooster or hen??

[braden38351]

 

[The hen breeder]

Judging by the size of it's comb, I would say it's a rooster

 

[braden38351]

I bought what I was told were three large laying hens and put them in with the chickens I already had (almost four months old) and the one I took a pic of is fighting with them. I didn't know if they were just establishing pecking order or if I had another rooster