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A church youth leader is charged with sexual assault of a child and online solicitation after an alleged sexual relationship with a teenager.

Police said James Ackley, a 25-year-old youth leader at University Park United Methodist Church in Dallas, Texas, had a relationship with a teenager younger than 17.

According to the probable cause affidavit, the relationship began in August 2012 at a retreat he was chaperoning.

The victim told police that "... during the retreat they held hands and kissed, but was unable to do anything else because Defendant Ackley had a girlfriend who was also attending the retreat."

When they returned home, "they would exchange text messages describing sex acts that they would perform on each other," she told police.

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The victim told police the two had sex in his truck in October at a parking lot outside St. Michael's Church.

In a letter to parishioners, UPUMC said it was working with police:

"We will also continue to take action to protect the children and youth of our church family by providing them a safe and secure environment," the church wrote. "Our hearts and prayers go out to all involved as we seek the Spirit's guidance, healing and care at every turn."

Ackley did some contract work at Bishop Lynch High School, helping with lighting events, and substituted on two half days. He was not a full-time school employee.

UPUMC said he underwent training in order to be a youth leader and a background check.