The victims' families did not return calls for comment, but Cervera said news of the arrest after so many decades brought them both relief and fresh pain.
"There's a sense of closure," Cervera said.
"There's a sense that we are reopening old wounds as we work with the families through the case."
Broadnax, who has a lengthy criminal record for burglary and assault in New York, was arrested at a homeless shelter for veterans on Monday by New York police. Broadnax's attorney did not return a call seeking comment.
Virginia Beach prosecutors said Broadnax waived an extradition hearing and will be transferred to Virginia to stand trial. Broadnax's former stepdaughter told The New York Times that he had served in the Army and had been incarcerated in Virginia before he married her mother.
The double slaying was a major case in the Virginia Beach area, prompting the department to assign nearly all of its detectives to the case in 1973, according to an Associated Press report.
"We did everything we could," former Virginia Beach police detective William Haden told the AP in 1998.
"We flew in the helicopter, we searched rooftops, we climbed into manholes."
Pietropola and Seethaler, who went to high school together, spent several days at Farrar's Tourist Village and were set to leave when a motel employee found their bodies just after noon on June 30, 1973, according to news reports at the time. The women's bodies were found in separate bedrooms of the cottage.
Both had been strangled, either by hand or with a piece of cloth, according to an AP report. Seethaler was shot once in the cheek and once in the temple, the report said. Her neck was also slashed.
Pietropola was shot three times in the side of the head, the AP reported. Both women were nude from the waist down and were believed to have been killed early on the day they were found. Other media reports said the attacker may have entered the cottage through a window.
Mike Mather, a former reporter with local television station WTKR, explored in 2011 whether the killings may have been connected to at least 10 others in Virginia Beach between the mid-1970s and mid-80s. All of the victims were young, white women, and most had disappeared from the waterfront in Virginia Beach.
"They had always considered that a possibility," Mather said of detectives he had spoken to over the years.
"That was a suspicion at the time, but they never had any hard evidence."
Virginia Beach police spokeswoman Linda Kuehn said that detectives have no evidence the cases are linked but that detectives would explore the possibility if new evidence points in that direction.
"We don't have anything to look at right now," Kuehn said. "It's obviously something they would look at."