The Metropolitan Transportation Authority identified the victims Sunday as Donna L. Smith, 54, of Newburgh; James G. Lovell, 58, of Cold Spring; James M. Ferrari, 59, of Montrose; and Kisook Ahn, 35, of Queens.
As CBS 2's Jessica Schneider reported, a community prayer vigil was held Monday evening in Riverdale overlooking the Spuyten Duyvil station, which is near the site of the derailment.
"Our community has been deeply pained by this horrific event," Rabbi Avi Weiss said earlier Monday. "We will be gathering not only to offer prayers of healing, but thanksgiving to emergency workers who heroically saved so many lives."
Co-workers and neighbors said Smith, who lived alone, was a paralegal at a nearby law firm and was active with the Girl Scouts of America.
"Incredibly sad," co-worker Beverly Byrne told 1010 WINS' Mona Rivera. "I can't bring myself to go back to her desk yet."
Byrne said Smith was on the train with her sister, who survived the crash. She said the sisters were best friends.
"Going into the city, her sister sings in a group and they were going to be performing," she said.
Lovell, an audio technician, was traveling to midtown Manhattan to work on the Rockefeller Center Christmas tree, said longtime friend Janet Barton. She called him beloved and said he also enjoyed wind surfing and playing guitar.
Lovell also worked as an audio technician for NBC programs, including the "Today" show, for more than 20 years.
"He was not only a skilled technician but also one of the nicest guys you ever met," wrote "Today" executive producer Don Nash in a statement.
State Sen. Greg Ball said Lovell was a caring member of his community and a family man. Lovell was the husband of Philipstown Councilwoman Nancy Montgomery.
Montgomery released a statement Monday night.
"Jim Lovell was a dedicated father, a caring husband, and a loyal friend. He had a passion for his work in the media and for the friendships he made and cherished. His spirit and sense of community can never be replaced," she said in the statement. "We would like to express our thanks for the overwhelming outpouring of love and support from our friends, our family, and our hometown. You have been present for us so often during our lives, and especially now. We are grateful."
Lovell is also survived by three sons, Hudson, Jack and Finn, and a daughter, Brooke, Nash said.
"Words can't express how much my father meant to me. It's safe to say he molded me into the man I am today," Lovell's son, Finn, 17, posted in an Instagram message about his father. "I love you and I miss you. I can't believe you're gone. This feels like an awful nightmare that I can't wake up from. Rest easy dad, I love you."
Montgomery appeared along with her sons with Lovell, Finn and Jack, for an interview with Anderson Cooper on CNN Monday night.
"I want people to know that Jim was interested in what everybody was doing," Montgomery told Cooper. "He was pure goodness and, he lived that, and showed that and gave that to his boys every single day. He gave that to his guys that he worked with. He gave that to his family and his brothers, his nieces and nephews. He gave that to his beautiful daughter. I want people to know how good he was.
Finn Lovell said he did not want his father to be labeled as the "victim" of an accident.
"I just want to say that my dad was not a victim. I don't want him to be known as a victim. Jim Lovell was so much more than just a victim. He was a loving father, great dad, best friend, uncle, great coworker -- just always had a smile on his face; never had anything bad to say about anyone; one of the best people you could have ever met," Finn Lovell said. "I just want to say that I am so proud and blessed that I was able to call him my father."
Another private memorial was held for one of the victims in Ossining on Monday afternoon, CBS 2's Andrea Grymes reported.
Friends, Families Remember 4 Killed In Metro-North Train Derailment
Coworkers remembered Ahn, who lived in Woodside, as an exceptional nurse on the night shift at Sunshine Children's Home and Rehab Center in Ossining.
"The nurses will tell you no matter how hard that shift was or how sick the children were, she always had a smile. She never left shift without saying goodbye to everybody," administrator Linda Mosiello said.
Ahn had just finished her shift and was on her long commute home when she died, Grymes reported. The staffing company she worked with said it is doing all it can to help her family get emergency visas to fly to the U.S. from South Korea. Her co-workers have already started raising money to help them, Grymes said.
At Ferrari's Montrose home, a sign on the front door requested privacy. But his neighbors could not believe that he was gone.
"It was a shock to everyone," said Ferrari's friend, Renata Martello. "I'm still in shock."
Ferrari is survived by a wife and daughter, Grymes reported. One family friend said he was very devoted to his family.
"He did everything for them, the finances, fixed everything," Vinicius Settepani said.
Ferrari was on his way to work, taking the same train he's taken for years from his Montrose home to Midtown, where he worked as a building superintendent, Grymes reported.
Gov. Andrew Cuomo expressed grief over losing four New Yorkers.
"We want to find out what the specific cause of the accident was to see if there is anything we can learn from it to make sure a tragedy like this doesn't happen again," he said.
Autopsies were scheduled Monday for the four victims.
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