On Monday, the sea of support for family, friends and other officers who worked with Rivera continued, CBS2's Elijah Westbrook reported.
The mood was somber all morning in front of the 32nd Precinct, where Rivera worked. Dozens on their way to work stopped by and paid their respects at a growing memorial honoring the 22-year-old officer's life.
More than 100 candles and flowers sit just feet from the entrance of the precinct.
"It's sad, you know, and they've been in my prayers because that's very sad. I've lived here practically my whole life, so, my heart just goes out to them," Sonya Hickman said.
"These individuals were somebody's husband, somebody's brother, somebody's son and so there are a lot of us who appreciate what they do for the community," Joy Williams said.
Williams came to drop off donations, including comfort food. Her father was a homicide detective with the NYPD. She said Rivera's death truly is a shared loss.
"He has been stolen in a way from his community, his department, his family, and that's just tragic. My heart is broken," Williams said.
Some residents who stopped by were still in disbelief about the loss and brazen act of a man who critically injured Officer Wilbert Mora and killed Rivera.
"I've got a grandson older than him, and that's just devastating, very sad. I pray for his mother," Marian Blackman said of Rivera.
"No one deserves to bury their loved one that young, by someone who wants to harm our city," Jacqueline Harrison-Shepard told CBS2's Kevin Rincon. "When a family losses a child, it hurts."
The gunman in Friday night's shooting, 47-year-old Lashawn McNeil, died at Harlem Hospital on Monday, sources told CBS2. The weapon he used was displayed by Mayor Eric Adams, as he vowed to crackdown on gun violence.
"This is the gun that killed our young officer on Friday night, a .45-caliber modified gun," Adams said.
The outpouring of support for the police officers was felt all weekend. Members of more than two dozen departments met Sunday in Westchester County and traveled by motorcade to the precinct.
"These things are never easy. Just another reminder why we have to keep that close bond and support each other. It doesn't get any worse than this," Dutchess County Sheriff's Office Det. Kurt Twaddell said.
Police organizations in Westchester donated to a fund for Rivera's family, which is still trying to come to grips with the tragic loss to gun violence.
"I just want the city to change. We're losing a lot of young lives," Maria Rivera, Officer Rivera's aunt, said.
Her message resonated loudly Monday in a wave of support that will continue in the days and weeks ahead.
"He was the first person that when he was a little boy, he always said he wanted to be a police officer," family friend Susana Rosario told CBS2. "He said I want to take care of the people, that's why he wanted to be police."
Officer Rivera's wake will be held Thursday from 1 p.m. to 8 p.m. at Saint Patrick's Cathedral.
The cathedral will hold a funeral Mass Friday at 9 a.m.
CBS2's Kevin Rincon and Elijah Westbrook contributed to this report.
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