The parents of former American swimming champ Jamie Cail said they are demanding answers about their daughter's death in the U.S. Virgin Islands and refuting autopsy findings that an accidental drug overdose killed her in February.

In an interview on ABC's "Good Morning America" on Wednesday, Cail's parents, Pat and Gary Cail, slammed the police investigation into their daughter's death in February, claiming critical evidence was "completely overlooked" and suggesting foul play may have been involved.

"What we are looking for is justice for Jamie. We're looking for truth," Pat Cail said.

Jamie Cail, who was raised in Maine and lived in the U.S. Virgin Islands for nearly two decades, was found unresponsive in February in a residence she shared with her boyfriend in St. John, the U.S. Virgin Islands Police Department said in a statement.

Cail's boyfriend, whose name was withheld by police, told investigators he found Cail, 42, unconscious after he left a bar and went back to their residence to check on her just after midnight on Feb. 21, according to police. The boyfriend told police he and a friend immediately rushed Jamie Cail to the Myrah Keating Smith Community Health Center, where she was pronounced dead, police said.

Toxicology results from the autopsy found that Cail died of "fentanyl intoxication with aspiration of gastric content," according to a statement the U.S. Virgin Islands Police Department released in August.

"Manner of death is accidental," the police department said in a statement, citing an Aug. 22 report from the medical examiner's office.

But Cail's parents said they believe their daughter's death was no accident and claim police have not been forthcoming with information. They said they haven't been given an official copy of the autopsy report despite repeated requests to obtain one.

"There is no way that she had fentanyl in her voluntarily," Gary Cail said.

Pat Cail added that her daughter "never did drugs. Never."

The parents shared with "GMA" graphic photos of their daughter they said were taken by a person they authorized to go to a funeral home to view the body.

"She had a black eye. She appeared to have had a blunt trauma to the forehead. It appeared that her nose had been broken. Her lips had blood around them," Pat Cail said, describing the images.

Gary Cail said, "We don't know if there's anything else on the rest of the body because we don't have the autopsy report."

ABC News has reached out to the U.S. Virgin Island Police Department for comment.

Jamie Cail was a star swimmer for much of her youth in Claremont, New Hampshire. As a teenager, she was a member of an 800-meter relay team that won a gold medal at the 1997 Pan Pacific Championships and in 1998 she notched a silver medal at the Swimming World Cup in Brazil.

Her parents said compounding their grief is the knowledge that their daughter was preparing to leave the U.S. Virgin Islands on March 14 to return to New Hampshire.

"She was coming home," Pat Cail said. "It makes no sense."