Just a month after speaking out about violence against Black women, a Chicago mother was found dead after her boyfriend strangled her, police allege.

Sierra Jamison, who had just celebrated her 30th birthday, was found dead on Monday inside a garage near her home. Charging documents obtained by HuffPost allege that Lawrence Boyle, 63, killed her while she was moving her car.

According to the charging document, Jamison and Boyle had been friends for about 10 years until their relationship turned romantic a few weeks before her death. Boyle has been charged with murder and had his initial appearance in court on Friday.

Prosecutors said Jamison returned home on the evening of Sept. 18 and told her mother that she was going to park her Jeep in a garage located in an alley close to her home.

According to the charging document, it was there that Jamison was met by her boyfriend, who allegedly strangled her, took her phone and covered her body with a tarp.

According to the document, Jamison’s mother grew concerned when her daughter did not return home and did not respond to phone calls or messages, and Jamison’s brother went to check on her.

When her brother entered the alley, he saw Boyle closing the garage door and noticed that Boyle had his sister’s phone. Boyle said she had thrown it at him and left to go to the store, according to the document.

Jamison’s mother then went to check the garage herself, where she found her daughter dead under the tarp.

According to the charging document, shortly after leaving the garage, Boyle called his ex-wife and admitted to strangling Jamison.

Boyle eventually turned himself in to the police on Wednesday and confessed to the killing, prosecutors said.

According to the document, Boyle told officers that he believed Jamison had a gun when he started strangling her, but continued even after realizing that she was not armed.

Just a month before her death, Jamison had been interviewed by CBS Chicago for a report on the high rates of violence that Black women face. She shared her experience as the victim of an attempted carjacking.

Jamison told the outlet that she was grateful she was saved when other women in the area took a stand against the suspect.

“They literally stepped in and helped me, it was a lot of Black empowerment, women empowerment that day,” Jamison said.

Jamison spoke passionately about protecting her Jeep Wrangler, which she said she bought for herself and felt like a symbol of the hard work and sacrifices she had made for herself and her son.

“My son had open heart surgery, he has a disability, so he means a lot to me,” she said. “And I’m not [going to] let this young man, with a knife at that, take anything I work hard [for] away from me.”

CBS Chicago reporter Dorothy Tucker described Jamison’s courage and strength as she offered condolences to her family.

Jamison’s aunt, Sadina Jamison, told CBS Chicago that Boyle was “someone she was comfortable around. This is someone she trusted, so she had no reason to fear.”

Jamison’s mother described her daughter to ABC Chicago as an “ambitious” person who was working as a phlebotomist and planning to attend nursing school. She was renting her home from a former co-worker and was looking to move with her 6-year-old son.

Following Boyle’s arrest, Jamison’s aunt told CBS Chicago that the family felt relieved that Boyle had been arrested.

“We are honoring her legacy. We are honoring her life. But today, we have a victory, because this person has been caught,” she said on Wednesday. “He is currently in custody, so yes, we can celebrate with a little bit of peace.”

Need help? In the U.S., call 1-800-799-SAFE (7233) for the National Domestic Violence Hotline.