Updated

Two gang members were charged with murder Monday in the death of a 15-year-old honor student who was shot near the Chicago home of President Barack Obama just days after she performed during his inauguration festivities in Washington, authorities said.

The two young men were described by police as "persons of interest" when they were taken into custody early Sunday, a day after first lady Michelle Obama and other dignitaries attended the funeral of Hadiya Pendleton.

Michael Ward, 18, and Kenneth Williams, 20, are now charged with one count of first-degree murder, two counts of attempted murder and aggravated battery with a firearm, Chicago police spokeswoman Melissa Stratton said. She said police believe both men are gang members.

Pendleton, a popular high school majorette, was with a group of friends who took cover during a rainstorm under a canopy in a park about a mile from the Obama home on the city's South Side. Police said a man hopped a fence, ran toward them and opened fire with a handgun. Pendleton was struck in the back and died later that day. Two others were injured.

Police have said none of the people in Pendleton's group were affiliated with gangs but that the gunman apparently mistook one for a member of a rival gang that had encroached on his gang's turf. The men charged Monday live nearby, Stratton said.

Pendleton's death was one of more than 40 homicides in Chicago in January, a total that made it the deadliest January in the city in more than a decade. But it was her background, her ties to the president's inauguration and the location of the park that thrust her death into the national headlines and put Chicago at the center of a national debate over gun control.

Not only did the first lady attend the teen's funeral, but the girl's parents were set to sit with Michelle Obama during the president's State of the Union address on Tuesday night. Obama is scheduled to return to Chicago three days later to discuss gun violence.

Homicides in Chicago topped 500 last year for the first time since 2008, stoking residents' concerns about gun violence and leading the police department to put more officers on the street and to focus more on combatting gangs.

Just as the December killing of 20 children and six adults at an elementary school in Newtown, Conn., brought renewed scrutiny of the nation's gun laws, the death of the popular Chicago teen has cast Chicago's gun violence problem in a new light.

Earlier Monday, Chicago Mayor Rahm Emanuel seemed to make just that point.

"The only time when the gun issue ever gets affected is when Newtown happens," he said. "What happens in urban areas around the country too often ... gets put to the side."

He said that while it's not wrong that massacres stir such debate, what happens on the streets of Chicago and in other urban areas "gets put in a different value system."

"These are our kids," he said, his voice rising. "These are our children."

Emanuel joined Police Superintendent Garry McCarthy and Cook County State's Attorney Anita Alvarez at an afternoon news conference to announce they would push for tougher gun laws that would increase the minimum sentences and require offenders to serve at least 85 percent of their sentences.

They say the law now allows offenders to be released after serving no more than half their sentences and sometimes obtain their release after a matter of weeks. Emanuel said he has been busy talking to state lawmakers about sponsoring the legislation.

To underscore the dangers that releasing such offenders so quickly, McCarthy brought photographs of men who were either arrested on murder charges or who were homicide victims themselves while they were on parole, often just months after they were convicted of gun charges.

"The gun laws are not working," said Alvarez. "They're not deterring gangbangers. We're not seeing gang member going to prison for long enough sentences."