The human remains recovered near a Tampa Bay area bridge Sunday have been identified as the second missing University of South Florida doctoral student, Nahida Bristy, Hillsborough County Sheriff Chad Chronister said Friday.

“The details of this investigation are gruesome, and the actions of the suspect are nothing short of pure evil,” Chronister said.

Bristy and fellow doctoral student Zamil Limon, both 27 and originally from Bangladesh, were last seen on April 16 in Tampa. Limon’s body was found on April 24 on the Howard Frankland Bridge.

Two days later, a black trash bag was spotted on the shoreline just south of where Limon was found.

Inside, investigators discovered another set of human remains in an “advanced stage of decomposition,” according to an arrest affidavit.

The bag was tied in a knot, in the same manner as the one containing Limon’s remains. Investigators also noted the body was wearing “similar clothing based on the unique style that Nahida Bristy was last seen on video surveillance,” according to the affidavit.

Like Limon, Bristy suffered multiple stab wounds. But the motive for the killings remains unclear. Detectives are “anxiously searching for that,” Chronister said.

Bristy’s family was overwhelmed with the news, her brother Zahid Pranto told CNN. “People should not be going through this kind of situation.”

The sheriff notified the family hours before the Friday morning news conference that the body was Bristy, Pranto said. Since then, his mother has been crying, and he’s been checking his father’s blood pressure closely.

“Our internal world is upside down right now,” he said.

Limon’s roommate, Hisham Abugharbieh, is in custody and has been charged with two counts of first-degree premeditated murder with a weapon in Limon and Bristy’s deaths. He also faces charges of unlawfully moving a dead body, failure to report a death with intent to conceal, tampering with physical evidence, false imprisonment and battery, in connection with Limon and Bristy’s deaths, the state attorney’s office said.

Abugharbieh, 26, will remain in detention as he awaits trial, a judge ruled Tuesday. Prosecutors had asked that he be held in jail due to the “brutal and violent nature” of the alleged crimes.

A medical examiner’s report said Limon suffered a deep stab wound to his lower back that penetrated his liver, among other wounds, according to court documents filed in Hillsborough County Court.

In addition to several stab wounds, Limon “was bound in front at his hands and at his ankles,” Chronister said. “His legs up towards his buttocks area was almost completely severed so he could be bent together … (making) it easier to place in a trash bag. He was left on the side of the road. As gruesome as this murder was he was literally left on the side of the highway like a piece of trash.”

Investigators had called Bristy’s family in Bangladesh last week to say they believed she may be dead, based on the amount of blood found in the apartment Limon shared with the suspect, Bristy’s brother told CNN affiliate WTSP.

Bristy’s family is working with the Bangladesh embassy to get her body back “as soon as possible,” Pranto said.

Abugharbieh was arrested the morning of April 24 at a home in Lutz, Florida, after law enforcement responded to a domestic violence incident involving a family member, the sheriff’s office said.

Bristy was a doctoral student of chemical engineering at USF. She had a master’s of engineering from the Bangladesh University of Engineering and Technology and a bachelor’s of science in applied chemistry and chemical engineering from the Noakhali Science and Technology University in Bangladesh, according to her LinkedIn profile.

Bristy’s dream “was to come back to Bangladesh, work here, do something big and contribute to society,” Pranto told CNN Monday. “She was the perfect sister. She was the perfect daughter of her family.”

Bristy and Limon “were exemplary students, building lives, creating community and contributing to our university in meaningful ways,” University of South Florida President Moez Limayem said in a statement today. The university is working with authorities in their investigation, he added.

Professor Mohammad Ismail, the NSTU vice chancellor, also grieved Bristy’s death, saying in a post on social media that she was a “talented and promising student.”

“Her untimely death is an irreparable loss to the university and the nation,” Ismail wrote.

During a USF vigil honoring the two students Friday, professors who worked closely with Bristy and Limon remembered them as bright, kind students who were cornerstones in their academic community.

“When I met her … I saw a student with a quiet smile, a soft-spoken demeanor and enthusiasm to begin her coursework. By every account from her friends, these qualities never left her,” said Vinay Gupta, the chair for USF’s department of chemical, biological and materials engineering.

Shortly after Bristy’s remains were publicly identified, Limon’s family said they hope the young woman’s loved ones “may find some measure of peace after receiving this confirmation.”

The gruesome killings of two students who traveled halfway around the world for higher education “contradicts everything what Florida and the United States stands for,” the sheriff said.

“People come here because everything is better here than in anywhere else in the world. And to have to make contact with the families and tell them that their their loved ones are missing, to call them back later again and tell them that we found them but they’re deceased, and then describe some details that they wanted to know how they were killed because they were stabbed, as many times as they were — it goes against every grain that Americans stand for.” (CNN)

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