While on patrol near E. 12th Street at 22nd Avenue, an officer saw two females in a heated argument that escalated into a physical struggle. Officer attempted to detain the females but they fled into a structure inside a homeless encampment. Oakland Police Units arrived on-scene. The females continued to argue inside the structure. As the officers approached, a male exited the structure and the officers contacted him to determine what the cause of the disturbance. The male, who was a party to the argument, said his girlfriend was in a heated argument with her mother over their living conditions. The officers were able to separate the two females and identified all parties involved in the disturbance. A warrant/record check showed the females were clear, but the male had a "no bail" warrant from BART PD for fare evasion and failure to appear in court. The male was placed under arrest on the warrant. A sergeant approved the arrest and debriefed the male. The male was booked into Glenn Dyer Jail. The females did not wish to pursue a complaint against each other and no further action was taken.