JEFFERSON COUNTY, Colo. -- A 14-year-old shot on Friday has died, the Jefferson County Sheriff's Office said Monday. School officials identified the teenager as Nathaniel Griego.

The shooting happened in a neighborhood near West Bowles Avenue and South Simms Street in unincorporated Jefferson County.

Deputies said a 15-year-old ran from the scene. He allegedly contacted his sister, who then called 9-1-1. The teen was arrested. He was initially being held on assault charges, but the Jefferson County Sheriff's Office said the charges are being amended to reckless manslaughter.

Deputies say the teens know each other.

"He [Nathaniel] was a sweet guy. He could always make you laugh or smile. And he just had the best personality," said Kaylee Obney, a friend of Griego.

Investigators haven't yet said if the shooting was an accident or intentional.

Support services will be available for students at Dakota Ridge High School.

The school system released a letter, reading in part:

"Teens often have questions about death and loss, so you may consider discussing any worries they may have. We will have mental health staff at the school available for any student who may need emotional support from 1-3 p.m. on Thursday, Jan. 5 in the counseling center and again on Monday, January 9 when students return to school. If your student is struggling with grief and needs extra support immediately, please contact either the Jefferson Center for Mental Health 303-425-0300, or the Colorado Crisis Service hotline 1-844-493-8255. The holidays can be a difficult time for many, so please access these resources as needed.

You can also find resources which may be helpful to support your child during this difficult time on the Jefferson County Mental Health website, http://www.jcmh.org/resources/.

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