MOSES LAKE — A Moses Lake man suspected of possessing and trading thousands of pornographic images and videos depicting children was arrested on separate charges Tuesday for attempting to solicit videos and images from a girl he knew to be 11 years old and attempting to arrange a sexual encounter with her.

Michael R. Walker, 28, admitted to police Tuesday that he had requested sexually explicit images and video from an 11-year-old girl from the Soap Lake area, and that he had sent her sexually explicit images of himself. He was charged Wednesday with communication with a minor for immoral purposes and sexual exploitation of a minor.

Law enforcement noted in bail recommendations that Walker is the subject of a previous “ongoing, very significant, investigation into his possession, and dealing in depictions of minors engaged in sexually explicit activity.” Walker has been the subject of 17 Cyber Tips from Google, and previous search warrants have resulted in thousands of known images and videos of child pornography, according to court documents.

In interviews with family members of the victim, police learned that Walker allegedly also sent friend requests to the victim’s older sister, mother and grandmother. The grandmother discovered her granddaughter was already Facebook friends with Walker, and learned that he had allegedly been sending the 11-year-old graphic sexual images.

The grandmother logged into the 11-year-old’s Facebook page and left it active. Before contacting law enforcement, she received two sexually explicit videos from Walker depicting himself.

The victim’s mother and older sister had previously communicated with Walker and sent him sexually explicit photos of other women from the internet. In an interview with law enforcement, they indicated that they had hoped to lure Walker to Soap Lake and were “willing to physically harm Walker at that time.”

Officers with the Moses Lake Police Department indicated that they were aware that Walker had reached out to other children across the state, attempting to befriend them and communicate over Facebook Messenger. Walker admitted to police that he had been collecting and trading child pornography for years, according to court documents.

Bail was set at $100,000. Walker has failed to appear for court appearances 15 times, according to court documents, and prosecuting attorney Carlee Bittle, representing the state of Washington, expressed concern that Walker would continue contacting minors if he was released.