Joseph Anderson, a 54-year-old man from Petaluma, was arrested for allegedly assaulting another man with a metal pipe in an unprovoked attack at Steamer Landing Park on Thursday evening. Police responded to a 911 call and found Anderson actively attacking the victim, although he had dropped the pipe by the time they arrived. Officers were able to control the situation without further violence and later recovered the metal pipe used in the assault. The victim sustained minor injuries but declined additional medical treatment. Anderson was charged with assault with a deadly weapon and booked into Sonoma County Jail. The Petaluma Police Department commended community members for their quick reporting of the incident.