Police reports obtained through a Freedom of Information Act request provide new information into the mysterious death of Mount Vernon resident Alexandra Castano 19 months ago.

A toxicology report completed on Nov. 19, 2021, determined Castano accidentally died from an acute fentanyl overdose.

The case has been closed and no one has been charged, according to a spokesperson for the city of Mount Vernon.

Castano's mother, Lucia Castano, is still upset with the way the Mount Vernon Police Department handled its investigation.

News 12 shared the report with her.

She said it was the most detail she has had about her daughter's death in almost two years."It's not making sense," said Lucia Castano, in an exclusive follow-up interview with News 12

.She spoke about what she thinks happened to her daughter and why she is demanding accountability for those responsible.

"I want to find out why the people killed my beautiful girl," said Lucia Castano.

The report states Alexandra Castano left her Summit Avenue home in Mount Vernon around 8 p.m. on Oct. 4, 2021.

She lived in the home with her mother and other families.Lucia Castano says she was making dinner for her and her daughter when Alexandra abruptly left the house. 

She did not say where she was going or why she was leaving.

The 24-year-old only sent one more text to her mom for the rest of the night.

"I'm sure my daughter died between 8:45 p.m. and 9 p.m. That's the only reason she wouldn't answer the phone for me anymore," said Castano.

Police reports indicate Alexandra Castano had been messaging multiple people for Percocets the night she died.

Lucia Castano said her daughter had anxiety but did not use drugs.

"That day Alexandra told her co-worker, 'I feel unsafe," Castano shared with News 12.

Shortly after leaving her house, a man from New Rochelle picked Alexandra Castano up from Mount Vernon and went back to New Rochelle.

News 12 is not naming this man because he is not facing any charges.

The man says noticed Alexandra Castano was "having difficulty breathing" and "she took an asthma inhaler," according to one page of the report.

He told police that Alexandra Castano declined to go to the hospital twice and insisted on going home.

At some point in the night, the man picked up a friend in New Rochelle and the three of them drove back to Mount Vernon.

"If someone can't breathe, it's your responsibility, you have to bring them to the hospital," said Lucia Castano.

She told News 12 she did not recognize either man's name from the reports.

One page of the report says the two men were captured on surveillance video outside Alexandra Castano's home around 10 p.m. that same night.

One of the men was seen and admitted to police that Alexandra Castano was unable to walk so he carried her "unconscious body" from the car to the front vestibule outside the home.

He admitted to "knocking on the front door to get someone's attention" before running back to the car and driving off.

He claims Alexandra Castano was still alive at this point, but Lucia Castano is not convinced.

"Alexandra was scared that day. Why was she scared that day?" she asked.

That same man who carried Alexandra Castano's body returned to the Summit Avenue home around 7:45 a.m. the next morning, according to documents, after finding her bag in his car.

He called the police using a fake name after finding Alexandra Castano's unresponsive body.

Minutes later EMS responded, waking Lucia Castano, who went downstairs only to find her daughter's body on the ground.

Lucia Castano says her daughter was shoeless with cuts on her feet, her bag was on a table, and her phone and glasses were sprawled beside her head.

"I don't know who killed my daughter," said Lucia Castano.Alexandra Castano was declared dead on the scene and showed signs that she died hours before.

The Westchester County Medical Examiner conducted an autopsy and did not find any signs of trauma or strangulation, but she had traces of cocaine in her system.

The toxicology report found fentanyl in her body.

"I'm sure the people used the fentanyl to kill my daughter," said Lucia Castano.

A spokesperson for the city of Mount Vernon declined our request to speak with police leadership about the case.

Only adding that the case was closed once the medical examiner's office determined Alexandra Castano's death was not a homicide.