MONTGOMERY COUNTY, Texas -- A 10-month-old Rottweiler named Hercules lived up to his namesake by biting a man trying to attack its owner.Catalina Humphrey said she was walking Hercules on a jogging trail along Sawmill Road near her home Saturday afternoon, when a man came up from behind and tried to attack her.Before she could react, Hercules pinned the man to the ground and bit him."The minute that he ran, I saw blood on the ground," Humphrey said.She said the man finally stood up, cursed at her and ran away.Investigators with the Montgomery County Sheriff's Office are searching for him."It's still hard for me to want to leave my house," Humphrey said, "because I'm still trying to wrestle with that."Hercules is showing his softer side now, by comforting his owner."I think he can sense that something is wrong and I'm sad because I'm still upset about everything," Humphrey said, "so he's been really good about letting me know that it's going to be okay when I feel down about what happened."Investigators are not certain what the suspect's motives could have been.They said the suspect was described as a clean shaven black male in his 20s, about 5'10", and weighing about 175 pounds.Investigators said he was wearing black jogging pants, a red shirt and a black baseball hat.The Montgomery County Sheriff's Office will be adding extra patrols in the area and is continuing the investigation.Sheriff Henderson encourages anyone with information to contact the Montgomery County Sheriff's Office at 936-760-5800 or Crime Stoppers at 1-800-392-STOP.