Long, 26, and her mother, Stephanie, were walking along Front Street in Northern Liberties when they were approached by two men. One grabbed Amber's purse and shot her in the chest when she refused to let go.
No arrests have been made in the case.
"We are protesting against the senseless murders happening in Philadelphia," said David Tatgenhorst, founder of Heeding God's Call. "The murder of this young woman is one of those senseless murders."
No one appeared to be home during yesterday's rally, and no relatives of Long's participated.
The group led prayers and recited a speech by the Rev. Martin Luther King Jr.
Since its founding in Philly in 2009, the group has worked to hold gun-shop owners accountable for illegal sales to straw purchasers. The group has expanded to Baltimore, Washington, D.C., and elsewhere.
"It isn't just occasional mass shootings in schools," Heeding God's Call co-chair Rabbi Linda Holtzman said. "It happens every day on every street.
"It's not just strangers on the street. It's people in our community."
Movita Johnson-Harrell, founder of the Philly-based Charles Foundation, said, "We want people to know that this is a problem that can affect anyone."
Johnson-Harrell created the foundation with her husband after their son, Charles, 18, was fatally shot in 2011. The group works closely with Heeding God's Call.
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