Fresno, California - Two California men face lengthy prison sentences following their conviction in unrelated child pornography cases investigated by U.S. Immigration and Customs Enforcement's (ICE) Homeland Security Investigations (HSI).

Steven Christopher Montes, 26, of Visalia, was sentenced Monday by U.S. District Judge Lawrence J. O’Neill to seven years in prison, followed by a 10-year term of supervised release, for possessing sexually explicit videos of minors.

According to court documents, from November 2013 through August 2014, and while serving as a band teacher at Riverdale High School, Montes secretly recorded sexually explicit videos of minors on campus. Montes obtained the videos by directing student band members to remove all of their street clothes, including undergarments, when changing into band or color guard uniforms inside a particular storage room where he had secretly set up a laptop computer to record them. In imposing the court’s sentence, the court stated that Montes’ conduct was “particularly reprehensible because of [his] position as an employee of the high school.”

This case was the result of an investigation by ICE HSI, the Fresno County Sheriff’s Office, and the Kings County District Attorney’s Office. Assistant U.S. Attorneys Brian W. Enos and Vincente A. Tennerelli prosecuted the case.

In the second case, Alexander Kastler, 28, of Simi Valley, was also sentenced Monday by U.S. District Judge Lawrence J. O'Neill. Kastler received a sentence of eight years and eight months in prison for possession of child pornography, following an investigation by HSI.

According to court documents, Kastler, who has a previous conviction for possession of child pornography and was residing at a sober-living facility in Kern County, was found in possession of a cell phone and tablet computer that contained thousands of images of child pornography.

Assistant U.S. Attorney Michael G. Tierney prosecuted the case.

“The sexual exploitation of innocent children is horrifying and we will never relent in our efforts to capture every predator we can,” said Ryan L. Spradlin, special agent in charge of HSI San Francisco. “We will continue to vigorously hunt down these criminals with our law enforcement partners and bring justice to those who have hurt so many.”

These investigations were conducted under HSI’s Operation Predator, an international initiative to protect children from sexual predators. Since the launch of Operation Predator in 2003, HSI has arrested more than 14,000 individuals for crimes against children, including the production and distribution of online child pornography, traveling overseas for sex with minors, and sex trafficking of children. In fiscal year 2015, nearly 2,400 individuals were arrested by HSI special agents under this initiative and more than 1,000 victims identified or rescued.

HSI encourages the public to report suspected child predators and any suspicious activity through its toll-free Tip Line at 1-866-DHS-2-ICE or by completing its online tip form. Both are staffed around the clock by investigators. From outside the U.S. and Canada, callers should dial 802-872-6199. Hearing impaired users can call TTY 802-872-6196.

For additional information about wanted suspected child predators, download HSI’s Operation Predator smartphone app or visit the online suspect alerts page.