WICHITA, Kan.—It started when a Kansas Highway Patrol officer pulled over two Kansas City, Mo., sisters for speeding near the Colorado border and found a small amount of marijuana in their vehicle. Three days later, one woman lay dying in a Kansas jail cell as her sister frantically tried to revive her. The sister alleges that jail guards stood by, ignoring her pleas for help.

Joy Biggs and her family were mourning the death of 58-year-old Brenda Sewell Friday and demanding to know why, according to Biggs, the two women were held for days in the northwest Kansas town of Goodland without being able to make a phone call after their arrest on Monday. And they want to know why guards at the Sherman County jail repeatedly refused to give Sewell the prescription medication she had carried in a pill box, together with the written scripts for them.

The Sherman County Sheriff’s Department put a notice on their website about Sewell. It confirmed her arrest on Monday and death on Wednesday and said the office believes that “proper procedure was followed in the confinement, treatment and care of Brenda Sewell.”

Sherman County Sheriff Burton Pianalto did not respond to a phone message or email from The Associated Press seeking comment. The statement said the case had been turned over to the Goodland Police Department for investigation.

Goodland Police Chief Clifton Couch declined to talk about the ongoing investigation other than to say their findings would be forwarded, probably next week, to the county attorney’s office for his review.

On Tuesday, Sewell spent the entire day vomiting, but she was not taken to the hospital until that evening once she started throwing up blood, Biggs said. But when she returned to the cell an hour later, Sewell told her sister the sheriff’s officer who took her to the hospital had told the nurse on duty that she was “faking it” and to just get some liquids in her and send her back to jail.

By Wednesday morning, Sewell was feeling worse, Biggs said. Her eyes began dilating bigger and bigger, and she started drooling out of her mouth. She tried to speak, but couldn’t form any words. As Biggs and another cellmate tried to hold Sewell up, they could feel her body getting limp and cold. Then Sewell quit breathing altogether, Biggs said. Together they laid her down on the floor and Biggs started to perform CPR on her dying sister.

“We kept hollering and hollering, ‘Please open the door and help us. She is dying; she is cold,'” a sobbing Biggs told the AP on Friday. “And they just won’t. They just kept looking in the window, looking in the window. Nobody came to help her.”

Paramedics eventually arrived and rolled Sewell onto a gurney to take her out of the cell. Biggs said she was later taken to another room and told her sister was dead. All the cellmates were then put into another cell that had a working phone Biggs could use to call out. She called a close family friend who was a lawyer.

“I called the lawyer first because I just thought that was most important because I felt like they had killed her,” Biggs said. “And then I made him call the family because I just couldn’t—I was so freaked out.”

Sewell carried medication for several medical problems, including hepatitis C, thyroid problems and fibromyalgia, said her brother, Rick Ray, of Kansas City.

Her siblings told the AP that Sewell had bought a motor home from some friends who live in Colorado who had driven it to Kansas City. Sewell and Biggs were driving those friends back home to Colorado. While in Colorado, which has legalized marijuana, Sewell bought the weed to ease her chronic pain and nausea. She had 31 grams of it in a sealed jar when she was stopped by the Kansas Highway Patrol for speeding, Biggs said. The officer claimed he smelled marijuana.

“It was a profile thing after he found out we were coming from Colorado because there was nothing visible,” Biggs said. “There was nothing going on. There wasn’t a smell in the car, I can guarantee you.”

It is unclear whether Biggs will face charges related to the case.