CHICAGO (CBS) — Two more CPS students were killed during a weekend that began with a visit from the president to bemoan Chicago’s violent streets.

Frances Colon, 18, a senior at Roberto Clemente High School, was gunned down Friday night in the 1100 block of North Pulaski. She was the unintended target of a shooter, Chicago Police said Sunday.

And Oscar Marquez, 17, a junior at Marine Math and Science Academy and the eldest of four children, died Saturday night after a gunman opened fire on the car carrying Marquez home from a shopping trip.

Six other people were injured in shootings since Friday night.

Judith Vazquez, who serves on Clemente’s Local School Council, called Colon’s death tragic and denounced all the recent shootings in which children have been killed.

“This is happening citywide, not just on the South Side, not just in Hyde Park where the president lives,” she said referring to the fatal shooting of Hadiya Pendleton, 15, a mile from the President Barack Obama’s house a week after she had performed in inauguration events in Washington, D.C. “The violence is bad citywide. It’s affecting the kids as a whole.”

Frances Colon was shot in the shoulder about 7 p.m. in the 1100 block of North Pulaski, police said.

“This girl was on track,” Vazquez said, referring other questions to the school.

Colon, of the 2900 block of West Armitage, was pronounced dead at Mount Sinai Hospital at 8:16 p.m. Friday, according to the Cook County medical examiner’s office. An autopsy on Saturday found that she suffered a fatal gunshot wound in her back and her death was ruled a homicide, according to the medical examiner’s office.

Her family could not be reached Sunday.

Oscar Marquez was returning from buying shoes at a local mall with his cousin when he was shot, his mother, Concepcion Marquez said Sunday in her Tri-Taylor neighborhood home in the 700 block of South Oakley.

His 18-year-old cousin, who was driving the car, was wounded in the arm, she said, and he was expected to be OK.

The cousins were near Western and Cermak about 6:15 p.m. Saturday when a gunman drove up, got out of his vehicle and fired on them, police said. They drove to Rush University Medical Center, but by the time they arrived, Marquez had died, authorities said.

Concepcion Marquez, holding her 18-month-old son in her apartment Sunday afternoon, said she didn’t know who shot her son and police hadn’t told her much. Relatives and friends filled the living room; more continued to drop by.

Oscar liked the Marine Academy and thought about enrolling in the Marine Corps after graduation, she said. Many of his cousins went to school with him, she said, adding that her son was not in a gang.

Fabian Lopez, a fellow junior at the school, said his friend was good at basketball and adored soccer — and despite the Marine Academy’s strict uniform code, wild soccer haircuts, too.

“It’s kind of hard to believe that he’s gone,” Lopez said.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2013. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)