"We wanted to assure them we're moving forward, that we're 100 percent behind them in making sure justice is done," he told reporters. "We stand with them."
There was no immediate comment from Autumn's parents, Anthony Pasquale and Jennifer Cornwell.
The suspects - identified by townspeople as Justin Robinson, 15, and Dante Robinson, 17 - are due in court Friday for a juvenile detention hearing.
As the wheels of justice gear up, a woman identifying herself as Annie O'Neill of Philadelphia, launched a national petition on change.org demanding that the brothers be tried as adults. The petition had received more than 3,000 signatures by late Thursday evening.
The site provided no e-mail link or contact information for O'Neill.
Dalton said Thursday his office will decide within a week or two if it will seek to try the brothers as adults.
The meeting between Dalton and Autumn's parents followed dueling statements from the two sides on Thursday.
The parents in interviews and a family spokesman, Paul Spadafora, said the prosecutor's office, the lead agency in the investigation, had botched the search. Spadafora, Autumn's paternal great uncle, also called for an investigation by the state attorney general's office.
Dalton defended the search, saying law enforcement officials had "poured their hearts and souls into this investigation and worked around the clock to find Autumn."
Autumn was last seen alive about 12:30 p.m. Saturday and was reported missing nine hours later when she did not make it back home past a family-imposed curfew. Officials said she sent a text message around 2:30 p.m., but was not heard from again.
Her body was found Monday night in a blue recycling bin at an abandoned house next to the Robinsons' home. Officials said Autumn, a BMX enthusiast, went to the house to exchange bicycle parts and was strangled.
In a Facebook exchange four days before Autumn disappeared, Justin invited her to his house to see a bicycle she had indicated she liked.
Justin, unlike his brother, also faces a charge of luring.
A granite sky clung mournfully to Clayton Thursday as the small town seemed to pause between the drama, shock, and anger of the previous five days and the expected emotional tumult of Saturday's funeral.
In Autumn's Victorian house on the 300 block of West High Street, her family was making final arrangements for her funeral before the meeting with Dalton.
Nick Contravo, a friend of the family, came out and said Autumn's parents did not wish to speak. Contravo said he was helping with the logistics for the funeral and was keeping focused on that.
"I'm not even watching television," he said.
On the 300 block of East Clayton Avenue, a half-mile away across Delsea Drive, two cars were parked outside the stucco Craftsman bungalow of the suspects' family, but no one answered the door.
Just around the corner, next to the Robinson backyard and in the shadow of a closed, ramshackle glass factory, a memorial to Autumn of votive lights, flowers, stuffed animals, and even pumpkins continued to grow.
John Strang, 70, who took part in the weekend search for Autumn, rode up on a small bicycle.
"This is our environment today. It's all violence, and life doesn't mean anything anymore," he said. "I hope the good Lord looks down at this and says, 'I'm going to step in do something here.'"
"She was going to be 13 on Monday," he said. "This is the end of her 13th birthday. But she's still with us. Just in a different place."
Michelle Hoffman also stopped by to visit the memorial and was asked if the town should cancel Halloween.
No, the woman said. "I'm sure she would want to have all the kids go out in her memory."
Meanwhile, in Trenton, State Sen. Richard J. Codey (D., Essex) introduced legislation that would impose a mandatory 5- to 10-year prison term for the first conviction for attempted child abduction. Current law gives judges discretion in sentencing first-time offenders.
Codey's news release announcing the legislation cited "the horrific murder" of Autumn as well as a spate of luring incidents in the state, most of them in North Jersey.
Contact Joseph Gambardello at 856-779-3844 or email@example.com.