Tammy Fox, a 38-year-old died from "serious injuries sustained in the crash," police said.

Tammy Fox was driving along Pine Street, a quiet tree-lined road in Scranton, Pennsylvania, when suddenly her car started picking up speed. Zipping by cars parked along the side of the street, Fox pumped the brakes of her black Hyundai Sonata as it hurtled toward an intersection.

Accelerating at about 60 mph, it plowed into parked cars and hit a tree, according to Pennsylvania State Police and the Scranton Times-Tribune. A witness saw brake lights flash, but the car still didn't slow down, according to the Times-Tribune.

Fox, a 38-year-old mother of five, died from "serious injuries sustained in the crash," police said. Organizers of a GoFundMe page raising money for her funeral expenses said Fox was killed "in a tragic car accident" on Aug. 22.

But on Tuesday, her boyfriend, John William Jenkins, who was described as Fox's "soulmate" in her obituary, was arrested and charged with criminal homicide.

"Ninety-nine percent of the time it's mainly operator error," Pennsylvania state trooper Bob Urban told WNEP. But a mechanical inspection of the car said otherwise.

After taking a closer look at the car, investigators discovered its brake lines, which transmit hydraulic pressure to slow a car, had been cut, the release said.

Authorities say Jenkins, 39, admitted to cutting the metal-coated brake lines on Fox's car the night before the crash. His reason: Jenkins had allegedly been trying to get a metal pipe that could be used to smoke crack cocaine.

By early Wednesday morning, the name of Fox's fundraising page had been changed to "Justice for Tammy."

"I just never bought that it was just an accident," Lisa Vargas, Fox's longtime friend, told WNEP.

Fox and Jenkins were both at home last week Tuesday night, WNEP reported, citing a criminal complaint. Jenkins told police Fox was "driving him crazy" because she wanted a pipe to smoke crack. Since he didn't want to go to a store to buy a pipe, Jenkins allegedly said he got under Fox's car and started "hacking away" at the parts to find something for his girlfriend to use, according to the Associated Press.

Jenkins allegedly said he "cut anything from underneath the vehicle that could be used to smoke crack," noting that he did not know anything about cars, WNEP reported.

Upon investigating Fox's car after the crash, police found that three brake lines had been severed and a fourth was crimped, according to the Times-Tribune.

In the days following Jenkins' admission, Fox's loved ones aren't buying his crack pipe story.

"I mean, can't you find something else around your house to smoke crack in?" one friend told WNEP. "Aluminum foil? Something else. I'm pretty sure if you're a career crackhead you can find something else besides a brake line to smoke crack in."

Grace Onderdonk, one of Fox's sisters, told the Times-Tribune that Fox had been sober for at least six months and often spoke at meetings. Stephanie Fox, another one of Tammy Fox's sisters, said her sister had been involved in helping women with their recovery, according to the Times-Tribune.

"She mentored people and took them into her home," Stephanie Fox said. "She would be the first one to help a homeless person if she saw them on the street . . . That was the kind of person she was."

Tammy Fox was well-known in the area as one of the key witnesses in a high-profile case against several former Lackawanna County corrections officers accused of sexually abusing female inmates, according to local media.

In text messages sent from Fox to Onderdonk less than 24 hours before the accident, Fox appeared to be upset with Jenkins, the Times-Tribune reported. "I need to get out of this house," Fox wrote in one message.

Following Fox's death, Jenkins reportedly began to behave violently, threatening to kill his sister and himself, according to the Times-Tribune.

Local media reported, citing a criminal complaint, that Jenkins allegedly told police he had "killed the victim and to arrest him now."

Gary Yates, who has known Jenkins for years, told the Times-Tribune he does not believe Fox's brake lines were cut on purpose.

"He wasn't in any state of mind to know what was going on," said Yates, who saw Jenkins the day before Fox died. "He was really bad. He couldn't walk straight or light a cigarette."

According to court records, Jenkins was denied bail and is being held at Lackawanna County Correctional Facility. He has not asked for a public defender and no attorney is listed. A preliminary hearing is scheduled for Sept. 7.

On Pine Street, one tree now stands out from the others. It's adorned with colorful balloons that bob gently in the wind and at its base rests an impressive arrangement of red roses. The tree is now a memorial for Fox, decorated with red roses, her favorite flower.

"Tammy was a free spirit who lived life to the fullest and gave selflessly to those around her," Fox's obituary reads. "She is gone too soon, but made the world a better place."