CBS affiliate WKMG-TV reports that investigators discovered more bones this weekend in the wooded area less than a half-mile from the Orlando home that the 3-year-old girl shared with her mother and grandparents.
Forensics teamed worked through the night, combing the dirt for any more remains, reports WKMG.
WKMG confirmed that animal bones were also found in the wooded area.
On Sunday Sheriff's spokesman Carlos Padilla said that the thick undergrowth has made for slow searching.
"They're being very tedious and very methodical," he said.
The area where the remains were found had been under water from this year's hurricane season. That poses a problem.
"Any time you have water at a scene, it just really destroys evidence," criminal profiler Pat Brown told The Early Show anchor Harry Smith. "First of all, it helps deposition proceed quickly. And then everything gets wiped away, you know, literally washed away and it's under water, so it's a disaster."
Brown also commented on the news that trash bags and duct tape were found at the wooded area, and that investigators were trying to get a match to similar items in the Anthony house.
"But here is the problem: It's been months," she told Smith. "People use trash bags pretty regularly, so if you ripped it off [a roll] and used it in a crime, chances are six months later you're not going to have that exact box, and the next box, say they brought the same brand, but everybody in the neighborhood buys the same brand."
Duct tape is also being examined as possibly having captured trace elements of a suspect. "It gets fingerprints, and you get your hair stuck on it," she said. "And you're in a rush so you might leave things, sometimes tear it with your teeth because you can't get it torn, then you have saliva. But how about that water? This is probably going to destroy everything on there."
The discovery of the skull was the first major break in the case in months, following the disappearance of Caylee in June.
Caylee's mother, 22-year-old Casey Anthony, waited a month to report her daughter missing. She initially told police that she left the child with a baby sitter, but detectives said her story was untrue. Anthony was charged in her daughter's murder on Oct. 14.
Although DNA results on the remains probably won't be released for several days, authorities and even Anthony's own attorneys are treating the find as if it is the little girl.
One of Anthony's attorneys, Linda Kenney Baden, said during a court hearing last week that "anthropological measurements and hair color" of the remains were said to match Caylee.
"We're getting very little access," Kathy Rice, a forensic anthropologist who is a member of Casey Anthony's defense team, told The Early Show's Smith. "We're getting no access at this point either to the remains or to the scene itself. We would just like to be there as independent observers."
"Would that be normal procedure, or would the local prosecutors want to at least get a positive ID first?" asked Smith.
"I've only served as a defense expert twice in my entire career, but on both of those occasions, we didn't meet this kind of resistance, we were allowed access," Rice said. "Of course, they're not going to be our best friends, but this is a bit more resistant than I'm used to seeing."
Sheriff Kevin Beary said that a search of the grandparents' home where the mother and daughter lived had also yielded links to the remains that he would not reveal. There are no other similar missing-child cases in the area.
Anthony is being held without bond at the Orange County Jail.
Brad Conway, the Anthonys' new attorney, told WKMG that while George and Cindy Anthony are being realistic about the probability that the body is little Caylee, "they pray that it’s not.
"Until there's a positive identification they're not going to give up hope. None of us will."
On Sunday, the suburban neighborhood near the Anthonys' home and where the remains were found buzzed with activity. Inflatable Santa decorations and holiday lights were an odd backdrop for the crime scene vans and satellite TV trucks.
Neighbors wandered over to take photos of a small, makeshift memorial for Caylee, which included a unicorn, a Cinderella fan and teddy bears of varying sizes and colors.
California bounty hunter Leonard Padilla - who had previously bailed Anthony out on lesser child neglect charges - stood by a canal, taking photos with well-wishers and handing out autographs. At one point, Padilla had conducted his own search for Caylee, and on Sunday, he pontificated on how long detectives might stay at the scene.
"Thank you for all of your help," neighbor Tim Lewis, 45, said to Padilla, shaking his hand.
Lewis, a 45-year-old flight attendant, admitted he has been captivated by the case.
"The truth has been very hard to find in this story," said Lewis, as his two daughters snapped photos of a cowboy hat-clad Padilla. "Maybe, finally, the truth is going to come out."