PHILADELPHIA (CBS) — After a violent Mother’s Day weekend in Philadelphia, police are asking the community for help in finding more than a dozen suspects. A deadly robbery is among the cases. The victim, Tyree Roundtree, was shot and killed in Frankford.

Police say 31-year-old Roundtree was arriving at his job at a construction site early Saturday morning when $1,500 and a single gunshot ended everything.

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Tonight, his family needs your help for justice as they privately grieve their loss.

Mother’s Day weekend proved to be violent in Philadelphia. Twenty-five people were shot, seven dying from their injuries, including Roundtree, a 31-year-old father to a 1-year-old little girl.

“Upon arrival they observed the victim lying on the highway, suffering from a gunshot wound to the back,” Philadelphia Police Capt. Jason Smith said.

Police say Roundtree was leaving his job at a construction site on Granite Street around 9 a.m. Saturday when a co-worker attempted to rob him.

“The descendant had in his possession, we believe, the day’s wages for the workers. He was responsible for paying the day laborers,” Smith said.

Police have identified the suspect as 25-year-old Nyhim Williamson.

“He has eight prior arrests,” Smith said.

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More than 48 hours later, Williamson remains on the run.

“We are praying constantly for his justice,” said Shareeda Roundtree, the victim’s sister. “He was loved tremendously.”

As the family of Roundtree is left to grieve, Tyree’s sister remembers her older brother’s ability to see the good in people.

“If he ever came into the room, he was the person that uplifted everyone,” Shareeda Roundtree said.

Shareeda Roundtree, along with six other families, is tasked with burying a loved one gone too soon.

“He did not deserve to die, his time was just cut too short. It’s going to affect a lot of people, pretty much no one is going to be the same,” she said.

Police say Williamson was last seen at the Frankford Transportation Center wearing a yellow hoodie and black mask.

Anyone with information is asked to call Philadelphia police.

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CBS3’s Alicia Roberts reports.