Residents of Brighton Park, a working-class Latino neighborhood with well-kept homes and bustling restaurants, said occasional gunfire had long been part of life, but only in recent months did they recall such use of high-powered rifles. The latest shootings, which left three people dead, came at a time of escalating violence and turf disputes among Hispanic gangs in this part of Chicago, according to the police. An analysis this year by The Chicago Tribune found 33 instances in a nine-month period where semiautomatic rifles were used in Brighton Park and nearby Back of the Yards, far more than anywhere else in the city.

Just in December, outraged neighbors held a vigil after four people were shot with an assault-style rifle near an elementary school. “Now this happens, six months later, and we ask the parents: ‘O.K. What do you all want to do?’” Marcos Ceniceros, an organizer with the Brighton Park Neighborhood Council, said. “And it’s like, ‘No, what can we do?’ There’s a lot of frustration.”

The Chicago police said there had been no spike in assault rifle shootings citywide this year. The police have seized 79 assault rifles in 2017, only a slight increase from last year. Across Chicago, 194 people have been murdered this year, about 6 percent fewer than during the same period in 2016, when violence rose to levels not seen since the 1990s.

The police said Hispanic gangs, suspected in this month’s bloodshed, were the most frequent users of assault rifles. One of the men charged in the shooting of the two officers had been out on bond after being charged with another gun crime — evidence, the police said, of a judiciary that is too lax.

“We know the gangs that have the weapons,” said Anthony Guglielmi, a Chicago police spokesman. “We know the gangs that are using the weapons. And in some form, we kind of know where the weapons are coming from.”