A Mesa man has been arrested after police found video of him having sex with a dog, during an investigation of an online sexual relationship with two pre-teen girls.

Court records show that on Tuesday, Mesa police arrested a man who allegedly was in a sexual internet relationship with two pre-teen girls. During the police investigation they not only found video evidence of that crime, but video depicting bestiality as well.

Kansas officials on March 23 alerted Mesa police to a sexual relationship 21-year-old Aaron Thomas Usery was in with two 12-year-old girls.

A parent of one of the children told Overland Park police that their daughter and her friend were in an inappropriate relationship online with a man from Mesa since September 2014. The Overland Park police say evidence found on the victims' electronic devices had photos and videos of Usery, also known as "Zel the Wolf," that were sexual in nature.

The girls also sent him nude pictures and videos of themselves.

Mesa police seized Usery's computer and phone, and also found sexual pictures and videos of Usery and the girls.

During their investigation, Mesa police say they located a video showing Usery engaged in sexual activity with the family dog.

Usery was arrested Tuesday and faces charges of sexual exploitation a minor, providing obscene material to minors, luring a minor for sexual exploitation and bestiality.