West Covina man arrested after investigators find him in possession of more than 600 obscene photos of minors

A West Covina man is behind bars and police are searching for more potential victims after he was found to be in possession of hundreds of obscene images involving children. 

Investigators arrested 39-year-old Matthew Mullen after a weeks-long investigation on Friday, according to a release from the Department of Homeland Security's branch in Los Angeles, who worked with the West Covina Police Department. 

Mullen was arrested after a federal warrant was served. He was booked for possession of a minor in a sexual act/pornographic material after they learned that he had more than 600 obscene images. 

"Due to Mullen's volunteer efforts in local organizations, Investigators believe there may be additional victims," the statement said. 

Police are asking anyone who may know more or believes they were also victimized to contact them at (626) 939-8520.