CHICAGO >> Late at night this month, the pastor’s phone beeped with a text message from an anguished parishioner. Andre Taylor, the church member’s great-nephew, had been shot and killed.

“Dre had just turned 16,” the message to the Rev. Ira Acree’s phone read. “I think that it’s time to call for action and solicit help, have the National Guard to take over and patrol the Chicago streets.”

Four days earlier, he had received another text. A different parishioner’s granddaughter, Daysha Wright, a 21-year-old nursing student, had been shot to death in a car, leaving a 2-year-old son.

At his desk at Greater St. John Bible Church, Acree said he was bracing himself for the coming months. “Unless something radical takes place, it’s going to be a bloodbath this summer,” he said.

Chicago has long been troubled by violence, but homicides and shootings have risen sharply this year. Violent crime remains below the levels of two decades ago, and criminologists caution against finding trends in only a few months of data.

But City Hall, the police and community leaders are alarmed by the surge: As of Friday, 131 people had been killed here in the first months of 2016, an 84 percent rise in homicides from the same period in 2015. There had been 605 shootings, nearly twice as many than at this point last year.

The increase could hardly have come at a more difficult time. The city is at a pivotal moment for law enforcement, mired in a crisis over police conduct and discipline and over distrust of officers, particularly among African-American residents, who make up about one-third of Chicago’s population.

The Justice Department is scrutinizing the patterns and practices of the city’s police force; the mayor on Monday named an interim police superintendent to replace the department’s fired leader; and voters have rejected Cook County’s top prosecutor, defeating her in a primary on March 15. The release in November of a police video that showed a white officer shooting a black teenager, Laquan McDonald, 16 times caused long-standing anger about police conduct to boil over.

And Mayor Rahm Emanuel faces enormous challenges: tamping down a flood of crime while simultaneously repairing frayed relations with the people who live here, as well as addressing low morale among officers.

“Trying to rebuild and do all of that at the same time, when violence is going up, creates all kinds of additional struggles and issues,” said Kim Foxx, who defeated a two-term incumbent in the Democratic primary to be the next Cook County state’s attorney in a race that revolved around the McDonald case.

Weekends and summer nights have often presented the most danger here, but these days shootings feel constant. On March 14, three police officers were shot and wounded in an exchange of gunfire that left a suspect dead. The next day, three people were killed in a single hour. The next, people inside two cars were reported shooting at one another along Lake Shore Drive.

“I’m really tired of it, and tired of worrying,” said Gloria Johnson, 37, who serves food at a restaurant in Austin, a neighborhood where the authorities say violence has been particularly harsh. Like other parts of the West Side, Austin has long wrestled with economic distress, gangs and crime, and Johnson bears a long scar on her elbow from a bullet fired about a decade ago.

“But it seems like this year is just the worst of the worst,” she said.

The police say much of the violence in this city of about 2.7 million people is tied to gangs, which have become disorganized and have splintered into more factions. While shootings along Lake Shore Drive and near a W Hotel not far from Chicago’s Gold Coast have drawn notice, most of those dying are young men on the South and West sides, the police say.

Back-and-forth acts of violence between groups, often using guns, are common. And the authorities say threats are increasingly delivered through social media (a notion some officers here have begun referring to as “cyberbanging”), perhaps speeding up the pace of retaliation.

A long-running dispute between gang factions, the authorities say, was at play in November, when Tyshawn Lee, a 9-year-old fourth-grader, was lured from a South Side park where he was playing basketball into an alley where he was fatally shot, execution-style. This month, in what the authorities believe was a continuation of the fight, three more people were shot and injured, and Tyshawn’s father, Pierre Stokes, was charged.

Few agree on why bloodshed has surged so far this year. Some experts point to relatively mild winter weather, while others note that Chicago has had ups and downs over many years, including an uptick in 2012, when more than 500 murders were reported. They point out that the numbers in recent years have been below those in the early 1990s, when more than 900 murders were reported some years. And the police say the rate of murders has slowed some in March compared with earlier in the year.

“Trying to read too much into this is a grave mistake,” said Craig B. Futterman, a clinical professor of law at the University of Chicago. “We’re all just guessing.”

Some officers and residents said they believed that since the McDonald case — and other police shootings that have drawn attention nationwide — Chicago officers may have “backed off,” though others rejected that as an explanation for a rise in violence.

Since January, officers have recorded 20,908 instances in which they stopped, patted down and questioned people for suspicious behavior, compared with 157,346 in the same period last year. Gun seizures are also down: 1,316 guns have been taken off the streets this year compared with 1,413 at this time last year.

In an unusual video address meant to reassure Chicago officers, John J. Escalante, who has been the interim superintendent, told them, “We are aware that there’s a concern among the rank and file about not wanting to be the next YouTube video that goes viral.”

Dean Angelo Sr., the president of the local police union, said public scrutiny had an effect on officers. “They’re being videotaped at every traffic stop,” he said.

But the drop in street stops by the police could be tied to a departmental change that took effect in January, requiring officers to fill out a far more detailed form for each one. The change was imposed after the American Civil Liberties Union raised questions about whether officers were targeting minorities in their stops. The department recently simplified the required paperwork, and the number of stops has since been on the rise, officials say.

Escalante said in an interview that the department “can’t rely on what we’ve been doing, and we’ve got to start looking at things we can do.”

He said changes had been made, including dispatching 100 new sergeants to the city’s 22 police districts to oversee officers. He also said that he intended to intensify a program in which gang members are urged to end criminal behavior and are offered social services, and another that holds meetings with families of people on the department’s Strategic Subjects List, a database ranking hundreds of people deemed most likely to be victims or perpetrators of shootings.

But Escalante learned this month that he was not in the running to become the permanent superintendent of the department, and three recommended finalists learned over the weekend that they would not get the job, either.

The city has gone months waiting for a permanent replacement for Garry F. McCarthy, the superintendent who was fired after the release of the McDonald video, and while Emanuel announced that he had chosen Eddie Johnson, a longtime veteran of Chicago’s force, as the new interim leader, the department’s long-term approach remains uncertain.

In a statement, Adam Collins, a spokesman for Emanuel, said, “The task before us, and focal point of our efforts, is to rebuild that trust while continuing to expand our crime-fighting strategy and invest in proven prevention programming.”

Some are skeptical. “Right now, there’s no strategy,” said the Rev. Corey Brooks, a minister on the South Side. “Or if there is a strategy, whatever it is, it’s not working.”

At his desk, Acree, the pastor at Greater St. John, flinches slightly when his cellphone chirps with new text messages.

The police said Friday that they had made no arrests related to the deaths of the family members he has been trying to counsel. The authorities said a replica gun, drugs and money were found at the scene where Taylor was shot. They said Wright was apparently not the intended target of the shooting that killed her while she was the passenger in a car.

All of it, the pastor said, had left him with few words. “I make sure they know I will walk with them through this,” he said. “But there’s nothing much I can say. You don’t want to just try to calm people down, because you don’t want to give a false sense of security.”

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