NEW YORK (NewsNation Now) — Heralded in recent years as the safest big city in America, New York City is closing out its bloodiest year in nearly a decade, struggling with a surge in homicides and a pandemic authorities say has helped fuel violence.

More evidence of that surfaced this week on social media. A group of about two-dozen young men was recorded attacking a BMW SUV, terrorizing the driver and his elderly mother in Manhattan.

New York City CrimeStoppers and the NYPD released video and stills hoping for quick arrests.

“It’s absolutely unacceptable,” said Mayor Bill De Blasio on Thursday. ”And y’know, you have these teenagers doing something that’s just wrong. Period. At least one has been arrested. The others will be.”

Police said the suspect in custody is 15-years-old and that they’re close to identifying at least two others. There were about 25 in the group that appeared to have attacked a taxi and its driver minutes before moving on to the SUV.

The attack comes amid growing concern in the nation’s largest city about increasing violent crime, some of it attributed to the pandemic and the resulting displacement of New York’s homeless.

NewsNation looked at some of the crime trends emerging in New York, Los Angeles and Chicago in 2020 and found some striking parallels.

Sexual assaults in all three were down considerably — by double digits — 19.4%, 24.7% and 22% respectively. Cases of felony assault were also either down or flat from 2019, but murders were up dramatically — 41% in New York, 33.5% in Los Angeles and 55% in Chicago.

Former NYPD detective Bo Dietl believes he understands the reason, at least in the case of New York, chalking it up to a justice system that treats criminals too lightly and police too harshly, with officers concerned about facing allegations of brutality, he believes, if they’re too aggressive in doing their jobs.

“Anywhere you walk around this city you’ve got roving gangs,” Dietl said. “Now whenever you do something, first thing that happens- all the boys come out with their cameras. When the cop tries to talk to somebody, they come out. And they’re already trying to attack the cop.”

Police leaders are eagerly anticipating the turn of the calendar, pointing to unprecedented challenges officers faced as COVID-19 brought the city to its knees.

Crime-fighting this year has been complicated by everything from budget constraints to the ubiquity of mask-wearing. Clearance rates fell as detective squads were stricken by the virus, and faith in law enforcement faltered amid police killings of Black people.

“We’re definitely coming out of that dark period,” Police Commissioner Dermot Shea said at police headquarters Tuesday. “The confluence of COVID into the protests into all of the debate about defunding the police — I can’t imagine a darker period.”

The spike in violence started just as the pandemic began disrupting lives and shuttering businesses, and it reached a crescendo over the summer, as the city recorded an average 57 killings per month in July, August and September. By comparison, each of those months averaged 33 homicides in 2019.