NAMPA, Idaho (KTVB) -- A Nampa man accused of sexually abusing a girl was indicted last week on 12 additional charges involving child victims.

Prosecutors allege 41-year-old Arion Diaz sexually abused at least six children between October 2010 and February 2015. The alleged victims ranged in age from 8 to 13 when the abuse began; in some cases, it continued for years, investigators say. According to the indictment, Diaz sexually touched his victims, showed them pornography and forced them to have sexual contact with each other in front of him.

When one child told a relative about the sexual abuse, Diaz drove him out to a lake and told him he would drown him if the child did not say he had made up the allegations, according to court documents. The suspect then forced the boy to call his relative and tell her he had lied about the abuse, according to a Nampa Police detective's report. Diaz was arrested March 4 after another one of the children told members of her church about the abuse. According to court documents, Diaz told officers during an interview that the children were lying and had made up their accounts of being abused. He was originally charged with five counts of lewd conduct with a child under 16.

The July 1 indictment adds an additional eight counts of sexual abuse of a child, three counts of aiding and abetting sexual abuse of a child and one count of intimidating a witness. Diaz is also charged with trying to violate a no-contact order after he was arrested. He is currently held in the Canyon County Jail on a $1 million bond and has pleaded not guilty. The suspect is due to appear in court for a motion hearing Tuesday.