I was going to say I thought he was just being protective of the hens but say the part about killing the chicken. Is he was game rooster? He needs to go!! You don't need a rooster to get your hens to lay.
He is a rooster...roosters tend to be violent and dominant may be the cause... They will defend themselves pecking and kicking and throwing themselves at you... Have you ever seen a cock fight... here in the U.S is illegal but ive seen some pretty brutal sh!* in Mexico