A West Covina man who was an active volunteer for community organizations was arrested for allegedly possessing more than 600 images of child pornography.
Matthew Mullen, 39, was arrested Thursday after a multi-week investigation by local police and the Department of Homeland Security, federal officials said in a news release.
Mullen faces charges of possession of child sex abuse material and possession of more than 600 such images.
He is being held without bail by West Covina police, and he is due to appear in Citrus Municipal Court on Monday.
Because of Mullen's "volunteer efforts in local organizations," investigators believe there could be more victims.
Anyone with information is asked to call Detective Iside at 626-939-8520 or the Homeland Security tip line at 877-4-HSI-TIP (447-4847).