CHICAGO (CBS) — Following a violent holiday weekend in Chicago, Police Supt. Garry McCarthy stressed that gun crime in Chicago was still on the decline over the past year, and sought to reassure parents of public school kids that Safe Passage routes will be secure when kids head back to school Tuesday morning.

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“We’re making progress, step by step by step,” McCarthy said on the CBS 2 Morning News on Tuesday. “Over the last 11 months, we’ve got more than 100 less murders than we had for the same timeframe a year before that; we’ve had almost 500 less shooting victims than we had the year before that.”

At least eight people were killed and 23 others wounded in shootings since Friday night over the Labor Day weekend.

“If we keep measuring day-by-day, if we don’t give those numbers any context, then obviously it becomes what’s going on, but what’s going on has been a problem in the city for a very long time,” McCarthy said. “We’ve set up systems to address it. We have a more holistic approach to crime reduction. It’s not just about what the Police Department’s doing, it’s about community involvement.”

Overnight, two teenagers were shot as they sat on a porch in the Auburn-Gresham neighborhood, along a street that is part of a designated Safe Passage route for Ryder and Gresham elementary schools.

A 16-year-old girl and and an 18-year-old man were sitting on the porch of a home in the 8500 block of South Paulina Street when someone got out of a car and shot them around 1:20 a.m. Tuesday. Their injuries were not life-threatening.

Police also were investigating a shooting at 8 p.m. Monday in the 5700 block of South Princeton Avenue, down the block from Sherman Elementary School. Fredrick Brown, 27, was shot multiple times, and died at John H. Stroger Jr. Hospital of Cook County.

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McCarthy noted, while several people have been shot along designated Safe Passage routes in recent weeks, none of those shootings have taken place when those routes are staffed by Safe Passage workers, community volunteers, police officers, and other city employees.

“Last week, we got through the mornings and the afternoons without any incidents,” McCarthy said. “The fact is that’s going to continue. It’s not an exact science, crime reduction, but when we’re not doing Safe Passage, we’re doing all those other strategies that right now have led to those numbers I just told you: 500 less victims, 100 less murders.”

The shootings along Safe Passage routes on Monday and Tuesday were the first shooting along a Safe Passage route since classes began last week, and took place several hours before the routes would have been staffed. The other shootings on Safe Passage routes happened before classes started at Chicago Public Schools.

“We haven’t asked the Bears why they haven’t won a home game yet this year, because the games haven’t begun,” McCarthy said.

McCarthy also reminded Chicago residents that the Police Department is accepting applications for the police entrance exam until Sept. 16. The department has lowered the application age from 21 to 18, and lowered the minimum hiring age from 25 to 21.

Unlike his predecessor, Jody Weis, who raised the hiring age from 21 to 25 three years ago to attract more mature recruits, McCarthy wanted to draw in a wider range of applicants for the next entrance exam in December.

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“We want to recruit from every demographic in the city, and we want the best possible pool of candidates that we can have,” McCarthy said.