Frank R. James was held with out bail on Thursday after prosecutors mentioned he posed a continued risk within the wake of a violent and premeditated assault on New York’s subway. His legal professionals, who mentioned their shopper had known as a tip line to give up, requested a federal decide to make sure Mr. James obtained psychiatric care in jail.

Mr. James’s temporary preliminary court docket look marked a brand new stage in a case that shocked a metropolis already on edge about subway crime. Without delay, the assault turned a morning practice trip right into a scene of chaos, injuring not less than 30 individuals, based on prosecutors. It was the bloodiest crime in New York’s public transit system in almost 4 a long time, and got here as many residents have been wading cautiously again into the routines of prepandemic life.

To some, the capturing underscored challenges dealing with Mayor Eric Adams, who has mentioned that high-profile crimes have elevated public nervousness over security to a few of their highest ranges in recent times — and that addressing these fears is crucial to the town’s restoration. On Thursday, prosecutors mentioned that the assault inflicted vital injury and disruption and that it may have resulted in a bloodbath.

They described every methodical step they are saying Mr. James, 62, took: from setting off a smoke bomb on a crowded subway automotive to unleashing a barrage of bullets and stripping off a disguise as he made his escape.

“The defendant terrifyingly opened hearth on passengers on a crowded subway practice, interrupting their morning commute in a method this metropolis hasn’t seen in additional than 20 years,” Sara Ok. Winik, an assistant U.S. legal professional, mentioned in court docket. “The defendant’s assault was premeditated; it was rigorously deliberate; and it precipitated terror among the many victims and our total metropolis.”

Mr. James, who’s charged with finishing up a terrorist assault on a mass transit system and faces as much as life in jail if convicted, mentioned little on Thursday, typically responding to the federal decide’s questions with a hushed “Sure.” As a result of it was solely his preliminary look, and he has not been indicted, Mr. James has not but entered a plea.

Outdoors the courthouse on Thursday, Mia Eisner-Grynberg, considered one of his court-appointed legal professionals, mentioned that her shopper deserved a good trial, warning that “preliminary experiences” from the police and information retailers “might be inaccurate.”

“We’re all nonetheless studying about what occurred on that practice, and we warning in opposition to a rush to judgment,” she mentioned. “What we do know is that this: Yesterday, Mr. James noticed his {photograph} on the information. He known as Crime Stoppers to assist. He informed them the place he was.”

The court docket look got here as native and state officers have been trying to reassure riders that transit methods stay secure, emphasizing that metropolis life stays far much less harmful than it was a long time in the past and inspiring New Yorkers to proceed taking the trains.

Subway ridership, nonetheless beneath 60 % of its prepandemic averages most of final month, fell within the assault’s quick aftermath. However Wednesday’s preliminary information supplied a hopeful signal: The numbers have been up by about 75,000 clients over Tuesday — for about round 3.1 million complete. They nonetheless remained beneath final week’s figures by about 159,000, a potential indication of lingering considerations.

Nonetheless, it may be difficult to establish a single reason behind fluctuating ridership, and the decrease figures got here on a day with nice climate, when fewer individuals wish to journey underground.

“We’re beginning to see ridership come again,” Janno Lieber, the chairman of the Metropolitan Transportation Authority, mentioned at a information convention on Thursday. “Even after the extremely disturbing information that all of us noticed this week.”

Whereas the broad particulars of Tuesday morning’s assault have been well-established, prosecutors haven’t described a possible motive for the violence. It remained unclear why a practice line that cuts by means of immigrant-heavy neighborhoods in Brooklyn, like Sundown Park, a house to many individuals from Asian and Latin American international locations, turned the goal of a brutal capturing.

However federal prosecutors wrote of their court docket submitting Thursday that whereas Mr. James’s prolonged arrest document — almost a dozen low-level offenses, together with reckless endangerment, larceny and trespassing — may appear “unremarkable,” it paints “an image of an individual with a penchant for defying authority and who’s unable or unwilling to evolve his conduct to legislation.”

Of their submitting, prosecutors mentioned Mr. James entered the subway system Tuesday morning in disguise, sporting a yellow onerous hat and an orange workman’s jacket with reflective tape.

On the practice, because it neared the thirty sixth Road station in Sundown Park, he fired “roughly 33 rounds in chilly blood at terrified passengers who had nowhere to run and nowhere to cover,” federal prosecutors wrote.

Particulars about Mr. James’s life have been nonetheless being pieced collectively: He had labored at Amazon for six months earlier than his position ended a couple of yr in the past, based on an organization spokeswoman, who declined to element how or why.

Regulation enforcement companies are scrutinizing hours of clues to his way of thinking that he supplied in disturbing movies posted for months on a YouTube channel and different social media accounts.

The movies depicted a troubled recluse, typically annoyed by problems with race, present occasions and world affairs, issues on which he typically delivered prolonged tirades. Additionally they revealed a person who may typically turn into fascinated by violent concepts, as soon as providing viewers directions for making a Molotov cocktail, based on federal prosecutors.

He mused not less than as soon as about mayhem in New York’s subway system. Different occasions, he questioned whether or not Mr. Adams may stop lawbreaking there. “He can’t cease no crime in no subways,” Mr. James mentioned. “He could gradual it down, however he ain’t stopping it.”

Federal prosecutors requested Thursday that Mr. James be detained till his trial, arguing that his “mere presence outdoors federal custody presents a severe threat of hazard to the neighborhood.”

After the capturing, the police found ammunition and different weapons in a storage unit and residence rented by Mr. James, prosecutors famous. The authorities additionally recovered an array of belongings from the practice, together with a Glock 9-millimeter handgun, three ammunition magazines and a bank card with Mr. James’s title on it.

Among the many assortment was a key to a U-Haul van that he had rented, which investigators later discovered about 5 miles from the station with a propane tank inside, prosecutors mentioned.

Mr. James was finally captured by the authorities on Wednesday afternoon, close to a McDonald’s within the East Village, about 29 hours into an expansive manhunt that featured a number of federal and state companies and a whole bunch of officers.

On Thursday, Mr. James’s legal professionals mentioned they didn’t object to his detention, however requested the Justice of the Peace decide to make sure that he obtained a psychiatric analysis and different medical care at Brooklyn’s Metropolitan Detention Middle, the place he’s being held, about seven blocks from the practice station in Sundown Park the place the assault came about.

Michael Gold, Sean Piccoli and Ashley Southall contributed reporting.