( CNN ) -- A 20-year-old Wisconsin man accused of attacking the mayor of Milwaukee with a metal pipe has been arrested , police said Sunday . Milwaukee Mayor Tom Barrett , seen in a file photo , was attacked Saturday night , police say . Mayor Tom Barrett was in stable condition Sunday at a Milwaukee-area hospital after he was attacked the night before at the Wisconsin State Fair in nearby West Allis , police said . Barrett was leaving the event with his family when he heard a woman crying for help , police said . When Barrett began calling 911 , the man who had been attacking the woman charged at him and began battering him with a metal pipe , police said . `` He not only risked serious injury but endured serious injury in order to defend somebody who was weaker than their assailant , '' Milwaukee Police Chief Edward Flynn told CNN Radio . Police arrested Anthony Peters in connection with the attack . Watch the mayor 's brother talk about what happened » . West Allis Police Chief Michael Jungbluth said the attack on the woman stemmed from a domestic situation , when an intoxicated Peters wanted to see his 1-year-old daughter , and had threatened to shoot himself and others . CNN 's Chuck Johnston and CNN Radio 's Shelby Erdman and Ninette Sosa contributed to this report .
NEW : Police arrested Anthony Peters , 20 , in connection with the attack . Police : Man beat Mayor Tom Barrett with metal pipe at state fair on Saturday . Barrett heard a woman screaming and tried to help her , dialing 911 . Man who had been beating the woman then started hitting Barrett , police say .