At the vigil (David Torres)

A crowd of friends, family and strangers gathered to remember the three people who were killed by a driver on a Bronx sidewalk while they were tick-or-treating on Halloween. Ten-year-old Nyanna Aquil died, as did her grandfather, Louis Perez, 65; Kristian Leka, 24, also passed away after apparently shoving his little sister out of the way. Mayor Bill de Blasio promised, "The NYPD’s Collision Investigation Squad will leave no stone unturned in its investigation."

Police say that before 4:53 p.m., a 2011 Dodge Charger that was going west on Morris Park Avenue had bumped the rear of a Toyota Camry, before "it crossed over the double yellow lines and continued to travel west on Morris Park Avenue when it mounted the sidewalk and struck six pedestrians before coming to a stop at 936 Morris Park Avenue." The car smashed into the group of trick-or-treaters and went through the house's front fence. Onlookers said that body parts were flying.

The Daily News reports that grandfather Louis, 65, "managed to push Nyanna’s sisters, Sanaya, 8, and Yasmina, 3, out of the way of the car that vaulted the sidewalk and hit the group."

According to the News, Natalya Perez, Perez's daughter and mother of Nyanna, told those at the vigil, "My dad was an amazing man. He helped me raise my children with love. He cleaned, cooked, took them to school every day... Nyanna was the best daughter in the world. She was gorgeous, she was sweet, she was a little bit shy. But she was going to be a star. She loved to dance to music videos."

WCBS 2 reports that Louis Perez had taken her children for another round of trick-or-treating while she was working; Natalya Perez said, "Life is short. Life is very precious and you have to always, always remember to love people, hug your loved ones don’t argue don’t fight, don’t waste any moments with them."

She added, "I know I look probably very stoic to some people. I have moments, when I cry, trust me, I do. But I know I have to be strong. I have two younger daughters, who need a strong mother in their lives. And they still have a long life to live, and that’s what I’m focused on right now."

Natalya Perez also posted photos on Instagram:

According to the NY Times,"Mr. Leka had just returned from work and, along with his fiancée, was beginning trick-or-treating with his 9-year-old sister, Fiona, who was dressed in a red-and-blue costume, when the car came at them. 'He was holding his sister’s hand and was trying to save his sister,' said a friend, who would give his name only as Florian. The fiancée, 21, was also hospitalized but expected to be released soon." Leka was an immigrant from Albania.

His friend Lendita Krasniti said, "Amazing guy, he did everything for everyone - he did not deserve to go young."

A GoFundMe has been organized for funeral expenses for Louis Perez and Nyanna Aquil. There is also a GoFundMe for Kristian Leka's funeral expenses.

The driver of the Dodge Charger, Howard Unger, 52, was hospitalized in stable condition. He has not been charged yet.

Police suspect that Unger experienced a medical episode. The NY Post reports, "Investigators “believe he had some sort of seizure,' a high-ranking source said.. 'He was driving, and he might have started his seizures, and he bumped the car in front of him... Some witnesses said they saw him violently shaking right before the accident.' The source said Unger had been taking an 'anti-seizure medication,' although his family said they were unaware of him having any medical problems."

Unger's mother Shirley told the News, "Not good at all. He’s not good at all. I don’t know what happened. I have no idea.” His sister also said, "It’s awful. It’s such a sad situation."

At the vigil (David Torres)

And Transportation Alternatives released this statement yesterday morning:

All of New York City should be horrified by the news of a motorist driving onto a Bronx sidewalk on Halloween and plowing into a group of children trick-or-treating. But no one should be surprised. In recent months, New Yorkers have read headlines about children killed in sidewalk crashes with outrageous regularity. This year, 13 pedestrians have been killed by curb-jumping drivers, including the three killed Saturday. And this in a city that has committed to a Vision Zero goal of ending all traffic fatalities and serious injuries.

Details are still emerging about this incident. But as we await the results of the NYPD's crash investigation, there is one thing we already know for sure: when drivers careen onto sidewalks, aggressive speeding is often to blame. We need more speed enforcement, and police and district attorneys must do more to hold deadly drivers accountable. This tragedy underscores the need for police to focus much more of the Vision Zero effort on reckless driving, and less on admonishing pedestrians to wear bright-colored clothing.

New York City cannot reach its Vision Zero goal without conistent enforcement to change the culture of reckless and careless driving. How many New Yorkers, how many children, must be struck and killed on sidewalks where they are supposed to be safe, before Mayor de Blasio treats this intolerable state of affairs as the crisis that it is?

Once again, we call on the Mayor to take a proactive approach to these sidewalk crashes - and that means going to the scene, and being with the families whose lives have been shattered. Because Halloween is an occasion that brings neighbors of all ages together in the streets, this crash can be an opportunity for all New Yorkers to understand the terrible cost of reckless driving. Mayor de Blasio must seize this moment and send an unmistakable message that the carnage on our streets must stop.

By Sunday afternoon, Mayor Bill de Blasio offered this statement, "Last night’s crash tore apart two families. These three innocent people were lost on a day normally filled with childhood laughter and joy. Our prayers are with them, their families, and those pedestrians still struggling with their injuries. The NYPD’s Collision Investigation Squad will leave no stone unturned in its investigation. We do not accept tragedies like this as inevitable. This could be any of our families. Each of us must contribute to making this a city where everyone, especially children, can walk our streets safely."