According to police, two men had attacked a 19-year-old woman a few blocks away, on 29th Street near Dauphin, pistol-whipping her after trying to snatch her purse.
The woman stayed on the scene and called police, and two officers drove her around the area in an attempt to find the punks who beat her, Little said.
When the three pulled up to Dawson's party, the woman identified Mann and Davis as her attackers.
But when the officers tried to arrest them, they became combative, and one tried to elbow a cop in the face, leading to a fight between the two, police said.
Then the cookout got really heated, with attendees descending on the grapplers. The initial officers called for backup after one was knocked to the ground and pummeled, Little said.
Marvella Davis, who is a sister to both Davis and Dawson, said that her brother and Mann were "victims of circumstance."
"No one knew why the police were there," she said. "They were coming up out of nowhere from every which way."
Marvella Davis disputed the assault victim's story - she said Mann and Davis were at the cookout the whole time. She said neither was armed, despite the woman's report that she'd been pistol-whipped.
Lt. John Stanford, a police spokesman, said no weapons were recovered during the arrests.
Stanford stressed last night that the investigation was ongoing, and that neighborhood residents were cooperating.
"We're not sure if there was a miscommunication, if they thought the officers were trying to wrongly apprehend them, because they may not have known this guy allegedly pistol-whipped a young lady a block away," Stanford said.
"There are very good and decent people in that neighborhood, but you may have one or two folks who let their emotions take control."
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