Police say a suspect made off with a man's wristwatch in The Ramble section of Central Park in May 2015. (Credit: CBS2)

NEW YORK (CBSNewYork/AP) — The Guardian Angels – the famous squad in stop-sign-red jackets and berets — strode through Central Park recently on guard for signs of crime.

It was a familiar sight a generation ago, when New York was plagued by lawlessness that police have worked for years to dispel. Yet Guardian Angels volunteers made a pointed return this month to Central Park for the first time in over two decades, citing a 26 percent rise in crime there so far this year.

Reports of several crimes have made the headlines in and around Central Park in recent months, including several muggings and an attempted kidnapping.

“We realize things are much better than they were” in the crime peak of the 1980s and early `90s, founder Curtis Sliwa says, but “we want it to stay that way.”

City officials stress that crime is down citywide, and the park is far safer than it once was.

Still, the renewed patrols by the Guardian Angels — known for both crime-fighting and controversy over their 35 years — are bright-red signals of unease about whether New York, touted for years as the nation’s safest big city, is slipping.

Sliwa and eight other Guardian Angels, ranging from graying long timers to a 20-year-old woman, trooped along roadways, paths and rocky, dark trails for hours one night this week, shining flashlights into thickets, asking people whether they’d had any trouble and eyeballing a quartet of teenagers who quickly took off on bicycles.

Onlookers’ reactions ranged from thumbs up to raised eyebrows. “Time warp!” one passing jogger exclaimed.

“I didn’t even know they were still in business,” Harlem resident Christine Adebiyi said, but “it’s great to see them here.”

After years of celebrating crime drops, the nation’s biggest city has seen killings rise by 9 percent so far this year, though serious crime overall is down 5 percent. Forty-six percent of city voters in a recent Quinnipiac University poll said crime was a “very serious” problem, a record going back at least to 1999.

A quarter-century after the “Central Park jogger” rape case made the park a symbol of urban danger, officials boasted in recent years that the 842-acre expanse was one of the safest urban parks of its size worldwide.

Despite this year’s increase — largely a result of robberies going from 11 at this point last year to 22 so far in 2015 — overall crime in the iconic park is down more than 80 percent compared with two decades ago, the NYPD said. Even with the recent spike, crime is lower than just two years ago, NYPD statistics show.

Mayor Bill de Blasio says the park remains “absolutely safe” and suggests police need no help from the Guardian Angels. “The NYPD is the best-qualified force to handle the situation,” he said this week.

Police circulating in patrol cars and shining high-powered lights maintain a visible presence in the park at night. But Sliwa says officers don’t penetrate into the secluded spots where criminals could lurk, an argument he underscored as the Guardian Angels passed an unilluminated NYPD light stanchion on a foot trail. Police later said the light is fully operational.

Guardian Angels feel much of their function is deterring crime, but if they see it, they’re ready to make citizens’ arrests, call police and defuse potential problems. This week, they prompted some young men to move on amid reports that the youths had been throwing rocks at people in the park and broke up a shoving match between two other men, Sliwa said.

A talk-radio host, Sliwa is an untrammeled critic of the first-term Democratic mayor, whom he accuses of hamstringing police. De Blasio has emphasized changing policing to build trust in minority communities and says the overall drop in crime shows his approach works, though he has had a fraught relationship with the NYPD.

To some extent, the Central Park patrols signal that those “unhappy with the direction that he wants to take the city are starting to mobilize,” said Queens College political science professor Michael Krasner.

The Guardian Angels began in 1979 and quickly expanded to other cities, welcomed by some people as a tough-minded neighborhood watch, derided by others as loose-cannon, publicity-seeking vigilantes.

By the mid-1990s, some chapters folded and the Guardian Angels’ reputation took a hit when Sliwa acknowledged fabricating some of their early exploits. Meanwhile, Sliwa was nearly killed in a 1992 kidnapping and shooting that mob scion John “Junior” Gotti was charged with ordering; prosecutors gave up after four juries deadlocked.

But the Guardian Angels endured and evolved: By 2006, they had a $200,000 New York state grant to do online safety education. They now count about 5,000 members in 18 countries, Sliwa says.

In New York, Guardian Angels still patrol parts of Brooklyn and the Bronx regularly. But shortly after Rudy Giuliani’s mayoralty began in 1994, they felt policing had intensified enough that they weren’t needed to fight crime in Central Park, Sliwa says.

“It got better,” until recently, he says. “That’s why you need to nip it in the bud now.”

(TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)