Charging documents detail the events surrounding the murder of 19-year-old Cynthia Hoffman, alleging the teenager accused of killing her blacked out and burned the gun he used to commit the crime.

Hoffman was reported missing by her family on Monday. Based on information from one of Hoffman's friends, her family told police that she was last seen at the Polar Bear Playground at Russian Jack Springs Park on Sunday afternoon. Police now know that was false; made up by 16-year-old Kayden McIntosh to mislead Hoffman's family and investigators.

According to Anchorage Police Department spokesperson MJ Thim, the turning point in the case was when officers talked with the mother of one of the friends Hoffman was with when she was killed. The mother told police that she overheard her daughter, identified by police as an adult woman, say that Hoffman was shot and pushed into the water.

Homicide detectives interviewed the woman on Tuesday. She told detectives that she, McIntosh and Hoffman were smoking weed in the Valley on Sunday when they started driving toward Anchorage, eventually stopping in Chugiak at a parking lot near Thunderbird Falls.

According to charging documents, the woman told detectives the three of them walked into the woods and were playing around. They agreed to duct tape each other and take photographs. Hoffman, referred to as "CeeCee" in the documents, was bound by her ankles and wrists; duct tape was also placed over her mouth.

"CeeCee started to panic," the documents state. "They removed the duct tape from CeeCee's mouth and hands. CeeCee began to tell them she was going to call the police and tell them that they had kidnapped her and sexually assaulted her."

The woman told police she had her Keltec 9 mm in her hand. The documents state that McIntosh took the gun from the woman and shot Hoffman in the back of the head.

"CeeCee was still on the ground and [the woman] believes she was trying to call police," the documents state. "[The woman] saw CeeCee twitching before McIntosh pushed her in the creek."

The woman told detectives that she and McIntosh went back to her vehicle in the parking lot. That's when McIntosh told her to text Hoffman's sister and make up a story about dropping her off somewhere. According to the documents, the woman complied because she was scared of McIntosh.

The pair then traveled to Anchorage, where court documents state McIntosh burned Hoffman's purse, some of her clothing, her ID and the gun he used to shoot her.

Homicide detectives also interviewed McIntosh on Tuesday. McIntosh also told detectives that the three of them were smoking weed in the Valley before driving to Anchorage and stopping in Thunderbird Falls. He also said that everyone agreed to duct tape Hoffman and take photographs.

"He recalls CeeCee started panicking and threatening to call the police on them," the documents state. "He stated he 'blacked out', but that he remembers shooting CeeCee and pushing her into the river. He remembers CeeCee twitching before he pushed her in the water and does not know if she died from the gunshot wound or from drowning."

McIntosh told detectives he didn't want the woman to go to jail. He admitted to burning Hoffman's personal items and the gun.

Hoffman's body was found by APD along the riverbank near Thunderbird Falls trail. Court documents stated her body was in the creek and her feet were bound together with grey duct tape.

The woman was released after being questioned. At the time of publication, she had not been charged with any crimes.

Police say McIntosh faces charges of first-degree murder and tampering with evidence. His bail was set at $100,000 cash.

At McIntosh's first court appearance Wednesday, it was revealed that if he posts bail, he will be put under house arrest with GPS monitoring. He is scheduled for a pre-indictment hearing on Thursday at 2 p.m.

APD stated the investigation is ongoing and it's possible more charges could be filed in the case.

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