BOULDER, Colo. (CBS4)– The 16-year-old accused of attacking a 71-year-old woman in Boulder County has been charged as an adult. Prosecutors officially charged Jeffrey Collins as an adult on Wednesday morning.

The details of what Collins has been charged with have been sealed. At the time of his arrest, Collins was facing felony charges including attempted first-degree murder and assault on an at-risk adult.

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Jeffrey Collins in court on Wednesday (credit: CBS)

Jeffrey Collins in court on Wednesday (credit: CBS)

Collins remained in custody on Wednesday. There were several people in court supporting Collins including two of his friends.

They declined to go on camera but did tell CBS4 they were surprised to hear what Collins is accused of and said those things seem out of character.

Investigators say Collins, 16, of Arvada, hit Katie Kulpa at her home near the town of Ward in the Boulder County foothills.

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The attack happened on Sept. 19 after Kulpa offered a lift to Collins and two of his friends. The trio was stranded in Lefthand Canyon.

Katie Kulpa with her son Curtis (credit: CBS)

Katie Kulpa with her son Kurtis Leverentz (credit: CBS)

Authorities say Collins wanted to steal Kulpa’s car and then suddenly attacked her while the group was at her cabin.

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The arrest affidavit has been sealed but some of the court documents were released before the judge sealed them. The judge has put any publication of those documents on hold.

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The defense has been given a week to file an appeal. After the 5 p.m. deadline on Oct. 5, more details in the case could become public.