A Maine man convicted in 1986 for his role in a notorious child sex ring has been sent back to prison for violating conditions of probation. Foster James McClure was ordered to complete the final eight years of his sentence on Tuesday for attending a high school robotics competition last month in the company of another registered sex offender. Prosecutors say the 56-year-old McClure violated probation by having contact with children under 18 and associating with another sex offender. Authorities say he attended the competition in Lewiston in April. People contacted police because they were videotaping competitors. McClure’s attorney tells the Morning Sentinel, the other man was doing the videotaping. McClure pleaded guilty in 1986 to charges including child rape and sexual abuse of a minor. He was released in 2008.