Police arrested a former Payson High School assistant softball coach Friday for allegedly engaging in sexual relations with a 15-year-old girl on the team.

According to police documents, McKell Shurtliff, 23, committed a series of unlawful acts during a three-month span in spring 2008. The abuse began in March last year when Shurtliff took the girl to her sister's house and performed oral sex on her. Police said there were four more unlawful sexual encounters.

The police investigated the case last November, but were unable to substantiate the evidence against Shurtliff until the girl disclosed information on the case last week. When interviewed by police, Shurtliff confirmed the girl's testimony, saying she knew at the time that the nature of the relationship was illegal, but that she pursued it because she loved the girl, according to police.

The school released Shurtliff from the coaching position last November when information from the investigation began to surface.