PINAL COUNTY, Ariz. - Mesa Police arrested a Pinal County Sheriff's Office detention officer Friday morning for sexual misconduct with a 15-year-old boy, Sheriff Mark Lamb said on Facebook.

According to court paperwork obtained Friday evening, police arrested Robert Hunter, 48, after learning through a tip from a social media website that Hunter was communicating with an underage boy and they had met for sexual contact in the past.

Detectives saw messages between Hunter and the 15-year-old, which were sexually explicit and talked about meeting to have sex, court paperwork says. 

The victim told detectives the two had met on a dating app in August of 2017 and August of 2018 and met five times for sexual encounters between August and November of last year. 

According to court docs, the first time they met Hunter acknowledged the victim was not 18 and the victim told Hunter his age, but continued with sexual contact anyway.

The victim disclosed 20 different acts of sexual contact with Hunter, knew what the inside of Hunter's home looked like and there is evidence in messages that Hunter knew the age of the victim, according to court paperwork.

Hunter admitted to using a dating app to "hook up" with other gay men but when the victim's name was mentioned, he said he didn't want to talk about him and refused to answer questions, court docs said.

According to a release sent out by PCSO, the detention officer is on administrative leave as Mesa PD conducts a criminal investigation, which could lead to more charges against the officer.

PCSO said the department is working with Mesa PD and will be conducting its own internal investigation as well.