The boys were charged with first-degree murder, conspiracy to commit murder, disposing of the body, tampering with evidence, and theft. The younger boy was, in addition, charged with a count of luring. Both were in police custody.
"We're strongly considering waiving them to adult court," Dalton said. ". . . Once we have all the information then we will make a final determination."
He added that he could not "comment or speculate on a motive" for the killing.
Investigators with the Gloucester County Prosecutor's Office, Clayton police, and New Jersey State Police executed a search warrant on the teens' home, where they recovered "personal belongings of Autumn in the juveniles' residence, including her BMX bike, along with other physical evidence, supporting these charges," Dalton said.
The suspects' mother had earlier contacted authorities about a posting on a son's Facebook page and investigators "were able to develop additional information which led to the discovery of Autumn's body late last night," said the prosecutor, declining to provide details.
The two suspects turned themselves in Tuesday morning. Authorities would not name them, but schoolmates and other residents identified the 15-year-old as Justin Robinson, a sophomore at Clayton High School who is one of three brothers. The name of the other suspect could not be immediately verified.
"Today we mourn the loss of a young girl named Autumn Pasquale whose life was tragically cut short before it really began," Dalton said. "Our thoughts and prayers go out to her parents, her family.
"It is my hope that the arrests today provide a measure of closure that the individuals responsible for their daughter's death will be held accountable," he said. "I also want to give my thanks to the residents of Clayton for their support during this tragic, tragic incident."
The prosecutor said he had "never seen a community come together in support of this family and this young girl like the residents of Clayton did over the last 72 hours, along with residents from throughout Gloucester County and the South Jersey area."
Dalton also praised the teamwork of 20 local, state, and federal law enforcement agencies that worked together over 72 hours.
The Borough of Clayton "today has been rocked," said Clayton Police Chief Dennis Marchei. "It is sad and tragic.
"However, this experience has proven to me that our community and the family of the victim have shown a spirit within our community, and our spirit has not been rocked," the chief said. ". . . At this point, I'm looking forward to the system working and justice will prevail for Autumn."
Tuesday morning, residents and onlookers gasped as they watched investigators retrieve Autumn's bike and other items from a white Cape Cod-style house in the same 300 block of East Clayton Avenue where they had earlier found her body inside a blue curbside recycling container.
The white BMX bike was the one Autumn was last seen riding on Saturday, investigators said.
"When the bike came out, everybody freaked out," said Paul Shimkus, who lives nearby. "People went, 'Oh, my God.' That was the defining moment."
Two blue bike rims and other bags of evidence also were brought out by investigators as they emerged shortly after 11 a.m. with residents looking on in disbelief.
"It's horrible," said Shimkus, whose son Nicholas is in Autumn's class and knew her for many years. "I live two blocks away. I'm just glad it's kind of over.
"Nothing like this happens in this town," he added.
Autumn - who went by two nicknames, Autti and Num-Num - was a seventh grader who enjoyed riding her BMX bike, playing soccer for a town league, and cheerleading for a local youth football league.
"I don't feel like she's dead," said Alaina Gompert, 12, a seventh grader who had classes with Autumn last year. "It doesn't feel real because she was here - like two seconds ago."
Alaina said she felt as if she would wake up and find "it was all one big prank."
Her parents came into her room to awaken her at 7:40 a.m. Tuesday with the news that Autumn's body had been found, she said.
"I knew something was up," Alaina said. "I could see it on their faces. Their eyes were watering."
Lisa Whartendy, whose 12-year-old daughter Victoria knew Autumn, said, "It's sickening. It's just scary."
Across the street from the house where the bike was recovered, neighbor Joyce Fisher also was trying to process the news.
"I'm scared," said Fisher, who had been canvassing the neighborhood Monday during the search for Autumn. "It's unnerving. It's devastating."
One of Autumn's cousins left teddy bears at a couple of locations, including where her bike was recovered.
At Clayton Borough Hall, Autumn's uncle and godfather, Paul Spadafora, declined comment Tuesday except to say, "Keep the family in your prayers."
Autumn was last seen at 12:30 p.m. Saturday, pedaling her bicycle from her West High Street home, where she lived with her father, Anthony Pasquale, a mail carrier, her two siblings, her father's girlfriend, and the girlfriend's children.
She was reported missing at 9:30 p.m. after failing to meet a family-imposed curfew.
Her body was found about 10 p.m. Monday by investigators for the Gloucester County Prosecutor's Office during a continuous search that began when she was reported missing.
"I know a lot of you are angry over what has happened and deservedly you have a right to be angry over what happened," prosecutor Dalton told the community Tuesday.
But, he added, "We have to put our anger aside and let justice take its course. . . . We'll get past this because we are strong."
Contact staff writer Edward Colimore at 856-779-3833 or firstname.lastname@example.org.