Shootings in New York City dropped by about 25 percent through the first half of this year compared with the same period last year, extending a downward trend after a spike in violent crime during the pandemic.

The sharp drop, which mirrored similar decreases across the United States, came amid widespread fears about crime in the city, which officials have blamed for keeping workers and suburbanites cloistered in their homes.

At a briefing on Thursday, Edward Caban, the acting police commissioner, said that shootings had declined for 13 consecutive weeks. The numbers were released at the beginning of summer, when violence historically rises, but he said he was “confident” that the department’s positive streak would continue in the summer.

“It is no coincidence,” Mr. Caban said. “From the beginning of this administration, we made the fight against gun violence our top priority.”

Through Sunday, reports of five of the seven offenses that the Police Department ranks as major felonies had gone down, while two increased, police data show. Murders, rapes and burglaries decreased by about 10 percent each; robberies fell nearly 5 percent. But car thefts increased 18 percent and felony assaults 6 percent.

Crime data is a “roller coaster,” said Jeffrey A. Fagan, a professor at Columbia Law School. Causality, he said, is “almost impossible to prove,” though police departments often take credit.

“Crime goes up, crime goes down, people are alarmed and the police department changes its tactics,” he said. “Whatever changes they’ve made, they don’t seem able to interrupt this cycle.”

“What they’re observing in New York is happening all over the country,” Mr. Fagan said.

As the pandemic swept the country in 2020, closing businesses, schools and confining people in their homes, violent crimes rose.

In New York, residents worried that the city was regressing into a violent past after years of consistent declines in crime rates. The dip in subway ridership and several violent crimes in the subways also led some New Yorkers to fear for their safety underground.

At the beginning of last year, as the pandemic eased and people began returning to their routines, the city struggled to stem an increase in violence.

Mayor Eric Adams, whose tenure began in 2022, made reversing the trend, specifically reining in gun violence, a central goal. Mr. Adams appointed a “gun violence czar.” He also expanded a jobs program and Saturday Night Lights, which offers activities for children between the ages of 11 and 18.

But the crime-fighting approaches of Mr. Adams and the Police Department have also been met with criticism.

Last year, the department announced an initiative designed to enforce what they called quality-of-life crimes, focusing on things like public drinking, urination and disorderly groups. Critics said that the enforcement is a return to “broken windows” policing, the enforcement of low-level offenses in an effort to prevent more serious crimes, which they said results in harassment.

In June, a court-appointed monitor found that anti-crime units, then under the leadership of the former commissioner, Keechant Sewell, were still stopping, frisking and searching too many people, despite assurances from Mr. Adams that new policies and training would prevent the problem. A report from The City this week found that there had been a 600 percent increase in vehicle pursuits in the year’s first three months.

For David Caba, vice president at Bronx Rises Against Gun Violence, the drop in gun violence that the department emphasized on Thursday reflects the work of social service organizations such as his.

Since the pandemic disruptions have ebbed, his teams, which operate in six zones within the Bronx, have seen shootings and homicides fall, he said. The zones are each made up of about 12 to 15 blocks that have grappled with high rates of violence. One zone has gone over a year without a single shooting or murder, he said.

“It takes everyone,” he said, adding: “It ain’t just one entity that’s going to come in and provide a remedy.”