ALAMEDA, Calif. (KRON) — “In my 25 years as a police officer, I have never seen anything as disturbing as this,” Alameda Police Chief Nishant Joshi said.

Two months after a woman’s remains were found along the shoreline of Bay Farm Island in Alameda, police said they made a major break in the case. A coroner identified the woman as Rachel Buckner, 27, of Pleasanton, investigators told KRON4 Thursday.

Her remains were found by a citizen who was walking along the shoreline near the Bay Farm Island bridge on July 20. Investigators discovered that the victim’s body had been dismembered and dumped on Bay Farm Island.

Alameda Police Sgt. Spencer Mountain said, “This one is pretty brutal. I have never had a dismemberment case.”

“Our investigators notified the FBI, U.S. Marshalls, the District Attorney’s Office and Pleasanton PD to track down the suspect,” Chief Joshi said.

Buckner was never reported as missing in Alameda County.

Police notified the woman’s family of her death. Chief Joshi said, “I was with my investigators when we made notification to the family. As you can imagine they were devastated.”

Investigators went to Pleasanton where Buckner lived with her boyfriend, 42-year-old Joseph Roberts.

Sgt. Mountain said, “The two of them had been dating. They might have even been engaged.” Roberts became the prime suspect, and on Wednesday, he was booked into Santa Rita Jail for first-degree murder.

Roberts and Buckner had no ties to the City of Alameda. “Neither one seems to be connected to anything here,” Mountain said.

Investigators are still working to establish a motive. DNA evidence linked Roberts to the killing, police said. “Primarily, the main evidence in this case is DNA. His DNA and her DNA linking them together,” Mountain said.

Roberts is locked in Santa Rita Jail in Dublin with no bail. He is scheduled to make his first court appearance on Friday morning for an arraignment.