A New York City police officer and an executive at an investment firm were among the four people killed by a gunman at a Manhattan office tower.

The officer, Didarul Islam, was working a corporate security detail on Tuesday at the Manhattan skyscraper that is home to the headquarters of both the NFL and Blackstone, one of the world’s largest investment firms.

Blackstone confirmed that Wesley LePatner, a senior managing director specialising in real estate, was fatally shot; security officer Aland Etienne was also killed, his labour union said.

The Rudin family, which owns the building and Rudin Management, said in a statement that one of their employees was a victim of the shootings but did not disclose the person’s name at the request of relatives.

Police officials said a woman was found dead on the building’s 33rd floor in Rudin’s offices.

NFL Commissioner Roger Goodell said in a memo to staff that an employee at the league’s headquarters was seriously wounded and in stable condition at a hospital but all other workers were safe; he did not name the person.

Authorities identified the shooter as Shane Tamura, 27, of Las Vegas, and believe he was trying to get to the NFL offices but took the wrong elevator.

Mayor Eric Adams said police found a note suggesting he had a grievance against the NFL over a claim that he suffered from chronic traumatic encephalopathy, a degenerative brain disease that has been linked to concussions in contact sports but can’t be diagnosed until death.

He had played high school football in California about a decade ago.

Police officer had been on the job for three years

Islam, who had been a New York City police officer for three and a half years, worked out of a precinct in the Bronx, where he lived with his family, officials said.

The 36-year-old immigrant from Bangladesh was married with two young sons and a third child on the way, police Commissioner Jessica Tisch said at a news conference.

Tisch said the gunman immediately opened fire on Islam in the building’s lobby.

“He was doing the job that we asked him to do,” she said.

“He put himself in harm’s way, he made the ultimate sacrifice.

“He died as he lived: a hero.”

Well-wishers visited Islam’s home on Wednesday, many carrying takeout food for relatives gathered inside.

Across the street, a public school where one or more of Islam’s children attended displayed a poster praising him as a loving parent and NYPD hero.

Acquaintances from his mosque also stopped by to pay their respects.

“He was a very friendly guy and a hardworking guy,” said Tanjim Talukdar, who knew him best from Friday prayers, but would always get a greeting when they met on the street.

“Whenever I see him or he sees me he says, ‘How are you, my brother?’”

“I was really shocked to see the news,” he said.

Blackstone executive was Yale graduate who specialised in real estate

LePatner, 43, was Blackstone’s global head of core plus real estate and chief executive officer of Blackstone Real Estate Income Trust, the firm said.

She joined the company in 2014 after working for more than a decade at Goldman Sachs, where she also handled real estate.

She graduated summa cum laude from Yale University in 2003 with a bachelor’s degree in history and served on the boards of several organisations, including The Metropolitan Museum of Art, the firm said.

A company statement said executives and other employees were devastated by her death and described her as “brilliant, passionate, warm, generous and deeply respected”.

LePatner’s family said their hearts were broken and asked that their privacy be respected as they mourn.

They also offered condolences to other families who lost loved ones in the shooting.

“We cannot properly express the grief we feel upon the sudden and tragic loss of Wesley,” they said in a statement.

“She was the most loving wife, mother, daughter, sister and relative, who enriched our lives in every way imaginable.

“To so many others, she was a beloved, fiercely loyal and caring friend, and a driven and extraordinarily talented professional and colleague. ”

Author Bruce Feiler said in a Facebook post that he was shocked, saddened and furious over LePatner’s death; he said they served together on a board at Yale.

“At 43, she was the most effortless and impressive person — you wanted to follow her wherever she went,” he wrote.

“A mentor to young women and generous friend to everyone who knew her, she was on the board of her children’s Jewish day school, recently joined the board of The Met, and just felt in every way like the kind of leader we all want and need in these unsettling times.”

Union calls security guard ‘a New York hero’

Manny Pastreich, president of Local 32BJ of the Service Employees International Union, said in a statement Tuesday that Etienne’s death “speaks to the sacrifice of security officers who risk their lives every day to keep New Yorkers and our buildings safe”.

“Every time a security officer puts on their uniform, they put their lives on the line. Their contributions to our city are essential, though often unappreciated; Aland Etienne is a New York hero [and] we will remember him as such,” Pastreich said.

Etienne had worked at the building since 2019 and also had a stint there in 2017, the union said.

State records show Etienne was licensed as an unarmed security guard since 2017.

Pastreich said the union was helping police and building management with the investigation and offering union members free counselling and support services.

He said other security officers and commercial cleaners in the union were working in the building at the time.