"If they have enough proof that he committed the crime in Peru, maybe, just maybe that might help to get him to confess in Natalee's case. It just might crack him," a Holloway family lawyer, Vinda de Souza, told the Associated Press.
A spokeswoman for Holloway's mother, Beth Twitty, issued a statement saying she "extends her deepest sympathy" to the Flores family "and prays for swift and sure justice."
"What breaks everybody's heart is this guy had something to do with Natalee and could have been stopped five years ago," Natalee Holloway's aunt Marcia Twitty told ABC News.com.
Van der Sloot was grabbed while riding in a taxi near the coastal resort city of Vina Del Mar. Police quickly recognized him despite the fact that his hair had been cut short and dyed red.
Peru's Interior Minister Octavio Salazar Miranda said, "We're confident this young man will pay for his crimes."
New details have emerged about the night that Flores died.
Van der Sloot and Flores, who was an avid gambler, were playing poker in a Lima casino late Saturday night and Flores was winning big, police said.
Investigators said van der Sloot invited Flores to his room at the Miraflores Hotel Tac to celebrate her winnings. A hotel employee later told police that she heard the couple arguing. Hours later, Flores was dead.
ABC News has learned that her body was not discovered for another four days because van der Sloot had prepaid his room for 14 days and instructed the hotel's front desk not to allow anyone into his room, including the cleaning staff.
Flores' father, Ricardo Flores, is a well known politician and former race car driver in Peru. He was burying his daughter at the same time that van der Sloot was being arrested in Chile. He said that his daughter's death had driven stake through the family's heart.
"It's not just about my daughter," he said. "There's a matter pending in Aruba and we don't know how many more remain unpunished."
"I think God used my daughter as an element so that another soul could rest in peace, so that the parents of this girl can rest in peace too, knowing that somewhere in the world justice was made for the killing of their daughter," Flores said.
"This man cannot continue to be out in the world killing people. This man needs to pay for his crimes," he said.
"Joran was able to laugh at the crime he committed in Aruba," the father said. "But in Peru he will not be able to laugh."