(CNN) -- Police believe 2-year-old Caylee Anthony was slain within days of the time she was last seen in June, and that her body was in the trunk of her mother's car for "a period of time," according to documents released Wednesday.
Casey Anthony is accused in the slaying of her 2-year-old daughter, Caylee.
The child's mother, 22-year-old Casey Anthony, faces charges including first-degree murder in her death.
The Orange County Sheriff's Office released a slew of documents and photographs in the case Wednesday.
They include myriad photos of the location where Caylee's skeletal remains were found in December, a wooded area about a half-mile from where the girl and her mother lived with Casey Anthony's parents. The documents also list evidence taken from that site, as well as from the Anthony home and Casey Anthony's car.
A supplemental report contained in those documents says that police believe Caylee was killed between June 16, the day the toddler was last seen, and June 27, based on evidence found in the car as well as evidence found with the child's body. Evidence also suggests "the body of Caylee Anthony was in the trunk ... for a period of time but removed prior to June 27, 2008," the report says. Watch what the new evidence reveals »
When she was notified at the Orange County Jail in December that the body had been discovered, Casey Anthony "allegedly had begun to hyperventilate and asked to be given some medication," the report said.
Other tidbits in the documents include that Caylee's body was found with a piece of duct tape covering her mouth -- tape that appeared to have been put on the child's mouth intentionally, according to the police report. Forensic analysis of the tape turned up "residue in the perfect shape of a heart," apparently from a sticker that had been placed over the duct tape, the report said. The sticker was found near where the remains were recovered.
However, no fingerprints were found on the duct tape, according to the documents. Watch: Caylee Anthony documents turned over to police »
A sheet of heart-shaped stickers with some missing were found by police executing a search warrant at the Anthony home, the documents said. In addition, forensic analysis showed that the duct tape found over Caylee's mouth was similar to that found on a gas can at the Anthony home.
In response to the information, Casey Anthony's defense team called the forensic evidence "junk science," pointing to a two-year study by the National Academy of Sciences. Results of the study were released Wednesday. In it, the academy said it found a "badly fragmented" forensic system that produces inconsistent results and needs a major overhaul.
The defense said its own experts would conduct an objective analysis of the evidence. They noted the duct tape, found to be similar to that on the gas can, is the most widely sold duct tape in the nation. "It is just as important to focus on the fact that there are no fingerprints on the duct tape, and there never was any red sticker of any shape or size found on the tape," defense attorney Jose Baez said.
A list of items found with Caylee's body is found in the police documents: A Winnie the Pooh blanket, clothing and pieces of a child's "pull-up pants," a type of diaper.
One photo is of an entry in a journal that appears to belong to Casey Anthony. It is dated June 21, but the year is unclear, as an opposite page bears the notation, " '03."
"I have no regrets, just a bit worried," says the entry. "I just want for everything to work out OK. I completely trust my own judgment and know that I made the right decision. I just hope that the end justifies the means. I just want to know what the future will hold for me. I guess I will soon see.
"This is the happiest that I have been in a very long time," the entry continues. "I hope that my happiness will continue to grow. I've made new friends that I really like. I've surrounded myself with good people. I am finally happy, let's just hope that it doesn't change."
CNN's Natisha Lance and Stacey Newman contributed to this story.