Police say an off-duty cop lost control of his vehicle and hit four pedestrians in Brooklyn early Saturday morning, killing one of them. Police say Nicholas Batka has been arrested on charges including manslaughter, vehicular manslaughter and driving while intoxicated. (Reuters)

Moments after an allegedly intoxicated off-duty New York police officer popped a curb on a busy Brooklyn block and crashed into a crowd of friends, authorities said, bystanders trapped him in his car and tended to those bleeding on the ground.

“Is he breathing?” one of them asked about a victim.

“Apply pressure,” another shouted.

Car horns blared and, soon, sirens started to scream.

The chaotic scene, which was captured on a cellphone video, unfolded in the early-morning hours Saturday in Williamsburg, where, authorities said, 28-year-old Nicholas Batka, who joined the police force in January last year, drove his Dodge Durango onto the sidewalk, striking four pedestrians.

One of them was killed and three others were severely wounded, according to a statement from police.

Batka now faces numerous charges, including vehicular assault, vehicular manslaughter, driving under the influence and criminally negligent homicide.

Just hours before Batka was scheduled to work a 7 a.m. Saturday shift for the Transit Borough Manhattan Task Force, police said, he was driving “erratically” when he made a right turn, mounting a sidewalk and barreling through a wrought-iron fence in front of a building, according to a criminal complaint.

Andrew Esquivel, a 21-year-old studying electrical engineering and computer science at Massachusetts Institute of Technology, died hours later — suffering critical injuries to his head and chest.

A fellow MIT student, 20-year-old Sophia Tabchouri, and a MIT graduate, 24-year-old James Balchunas, were also injured. Divya Menezes, a 23-year-old New York University student, suffered injuries to both legs, plus her arm and pelvis, police said.

“I ran over and this girl’s leg was in half,” bystander Ryan Carpenter told the New York Daily News. “I took my shirt off and tried to stop her from bleeding while trying to calm her. She kept screaming.”

Jaminah Kang, another witness, told the newspaper that the “EMTs had to get a saw to remove the man impaled on the railing.”

The victims were rushed to hospitals in Manhattan.

Kang told the Daily News that two other people in the group were walking ahead of their friends and were not injured in the accident.

“The other two friends were literally one step ahead of them, so they didn’t get hit,” Kang said. “It was unreal. It was like an episode of TV come to life. I wasn’t even thinking about what I was doing.”

When first-responders arrived at the scene, they found Batka sitting in the passenger seat.

A witness told investigators that after the accident, the officer tried to slide from the driver’s-side seat to the passenger’s side to get out of the vehicle, because the driver’s-side door was blocked. But bystanders held the other door closed.

“Don’t let him get out,” one person said in the cellphone video. “He’s going to run away.”

Some witnesses said Batka flashed his badge to passersby, according to the Daily News.

Authorities said he had “bloodshot, watery eyes, slurred speech and the odor of alcohol” on his breath, but he refused more than once to let officers test his blood alcohol level, according to court documents.

Batka was taken to Presbyterian-Weill Cornell Medical Center for minor injuries, according to the documents. Officials told Newsday that he was arraigned that night and posted $300,000 bail and was released.

It’s unclear whether Batka has an attorney.

Police said he has since been suspended without pay.

On Monday, MIT Chancellor Cynthia Barnhart wrote in a letter to the university community that several students were in a “grave accident.”

“On behalf of the entire MIT community, our deepest sympathy to Drew’s family and friends,” she wrote. “To Sophia and James, we extend our best hopes for their recovery and we offer them and their families any support we can. And to the larger circle of their MIT friends and connections, we join you in your shock and grief.”

New York University said the “NYU community is saddened by the news of this terrible automobile crash and its tragic toll.”

According to the Centers for Disease Control and Prevention, nearly 10,000 people were killed in alcohol-related accidents in the United States in 2014, which amounted to more than 30 percent of all traffic-related deaths that year.

Although statistics on and scholarly research of DUI incidents involving police officers are limited, a 2010 New York Daily News investigation showed that over an 11-year period, at least 55 active-duty NYPD officers were charged with driving while drunk and then took plea deals for non-felony charges.

“The number of cops convicted in drunken-driving incidents is an extremely tiny percentage of the 30,000-member force,” the newspaper reported. “But the incidents occur fairly regularly, year after year.”

Friends, classmates and colleagues began mourning Esquivel, a young man they called “an extraordinary thinker,” “intelligent” but “still a real person” and “one of the greatest people I have ever known.”

By all accounts, Andrew Esquivel, known as “Drew,” was a smart kid: an Eagle Scout and straight-A student who worked his way from his hometown of Healdsburg, in Northern California, to one of the top schools in the world for math, science and engineering — and he earned the prestigious James Family Foundation Scholarship to pay for it, according to the Press Democrat.

“It’s just devastating,” Scott Weidemier, Esquivel’s former wrestling coach at Healdsburg High School, told the newspaper. “He was obviously bright as can be. He just had the whole world in front of him.”

At MIT, Esquivel was a rising senior studying electrical engineering and computer science and was a leader in the wrestling club — named the university’s wrestling rookie of the year in 2014 and MVP in 2015, according to the Boston Globe.

The Globe reported that he was also a finalist for the National Collegiate Wrestling Association Nationals qualifier and a NCWA Northeast Conference finalist.

This summer, he was interning with a mobile marketing company, Appboy, in New York City.

“He would just be in his head, thinking about something, and then all of a sudden you would be like, ‘How did you come up with that?’ ” Harry Rein, 22, a friend and fraternity brother who worked with Esquivel, told the Globe.

“He is just such an extraordinary thinker.”

Another friend, 23-year-old Zac DelVecchio, recalled Esquivel as “one of the brightest people I have had the pleasure to know.”

“He was the type of guy who could make even the most serious of work situations into a fun and exciting time,” DelVecchio told the Globe, adding: “His contributions will always be a guiding star in what we do [going] forward.

“I pray for him and his family in this dark time and know that there will be a light to come. Rest well, Drew.”

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