A 19-year-old was sitting on her steps in North Philly. Then gunfire erupted, and a bullet claimed her life.

Ayanna Grabe sat on the edge of a futon in her living room Thursday morning, holding a tissue and dabbing at tears as she spoke of her 19-year-old daughter, Yaniyah Foster.

“She didn’t deserve this," Grabe said, staring at the front step where her daughter had been shot. “My daughter didn’t deserve this.”

Foster was struck in the head by a bullet Wednesday afternoon outside the home she and her mother shared on the 1000 block of West Thompson Street, police said. Three men were wounded in the same incident, one critically, and police said more than 20 shots were fired.

Foster was taken to Temple University Hospital, where she died hours later, police said.

A law enforcement source said two males, including a juvenile, have been arrested and charged in Foster’s death. Their names were expected to be released later Friday.

The homicide continued a violent beginning to the year. According to police statistics, the city had recorded 51 homicides through Wednesday, the most to date in any year since 2011, and through Tuesday, more than 160 people had been shot.

City officials — including new Commissioner Danielle Outlaw — gathered at City Hall on Thursday afternoon to discuss possible solutions to the epidemic of gun violence.

Outlaw, a mother of two sons, said she would be “inconsolable” if she lost them to gun violence. She also pledged that the department will be “a learning organization” and strive to use all the available tools and work with others "to break down the silence that too often impedes progress of community engagement and inclusion.”

And Council President Darrell Clarke called for public hearings to discuss the possibility of adding surveillance cameras around city schools in areas with high crime rates. The shooting on Thompson Street took place directly across the street from St. Malachy Catholic School.

“We have to do more to protect students coming to and from school, teachers and others who work in the schools, and residents who live in neighborhoods plagued by all of the gun violence,” Clarke said in a statement.

Homicide Capt. Jason Smith said the Thompson Street shooting was recorded on surveillance video. The footage showed two men walking southbound on 11th Street around 3:37 p.m. before turning onto Thompson Street, then immediately firing shots toward a group of people gathered outside Foster’s home, Smith said.

Foster and a man were struck, Smith said, while another man ran after the assailants on 11th Street and returned fire. A 25-year-old man sitting in his car was caught in the cross fire and struck in the head, Smith said.

Smith said that it was too early to be sure of the intended target but that 22 shots were fired from two handguns.

The three male victims were taken to the same hospital in separate vehicles, police said. Two of them, ages 23 and 25, were in stable condition Thursday. The man who was shot in the head remained in critical condition, police said.

Smith said that investigators found two guns inside one of the cars driven to the hospital, and that the calibers matched the type of fired cartridge casings found at the scene.

He said detectives were questioning several suspects, but declined to identify them or offer a possible motive.

Grabe said her daughter, a graduate of Ben Franklin High School, had come home from her job at the Greek restaurant Kanella Grill minutes before she was shot, and was supposed to return to the Center City eatery later to pick up a paycheck.

Grabe described Foster as loving, caring, and one of four siblings.

“Everybody loved my baby,” she said.

Ben Franklin teacher Keith Pretlow said Foster was bubbly, outgoing, funny, and impossible to miss. He said she often talked about her passions -- law and criminal justice -- and was debating whether to pursue a career as a lawyer or as a police officer.

“Her goal was to come back to her community and effect positive change,” said Pretlow. “She wanted to do some type of reform, to help marginalized communities.”

Caroline Christian, a manager at Kanella Grill, said Foster had worked as a runner for several months, but had taken to the family-like atmosphere among the staff and was continuing to grow and earn more responsibilities. Christian said she had planned to talk to Foster about elevating her to a server when she came back to the restaurant Wednesday evening.

“We’re all devastated,” Christian said, describing Foster as “shiny, and smiley, and sharp, and bright.”

State Rep. Malcolm Kenyatta, a North Philadelphia Democrat, was among those who came to comfort Grabe at the house. Kenyatta had been canvassing the block Thursday morning with antiviolence advocates Radee Hammett and Lorraine “Mrs. Dee Dee” Haw. Kenyatta said he grew up in the neighborhood and was fed up with discussion of violence prevention instead of action on the ground.

“I don’t want to do another dang news conference,” Kenyatta said. “The folks who live here — this is traumatic."

Grabe told Kenyatta she wanted to get out of the neighborhood, fearing she would not be able to bear living in the house where her daughter was killed. She wondered why ongoing disputes in the neighborhood put residents in peril, and why police were not on the block in the middle of the afternoon, even though schoolchildren were still around.

But most of all, she kept returning to the thought that her daughter was gone.

“It’s like they stole something from me,” Grabe said, crying as her head collapsed into her hands.

Staff writers Joseph A. Gambardello, Mensah M. Dean, Mike Newall, and Kristen A. Graham contributed to this article.