A former Hartsdale high school teacher has been sentenced to 13 years in federal prison after admitting he coerced two minors into sending sexually explicit photographs and videos, according to federal prosecutors. A judge also ordered 10 years of supervised release once he leaves prison.
Sexually exploiting children will not be tolerated in New York, and teachers and others in places of trust who engage in sex crimes have no place in our society. Any individuals with information concerning the sexual exploitation of children should contact Homeland Security Investigations.
— U.S. Attorney SDNY (@SDNYnews) March 18, 2026
Case and sentence
KOSTAS FEKKAS, who prosecutors say also used the names "Constantine Fekkas" and "C.J. Justice," was sentenced by U.S. District Judge Cathy Seibel after pleading guilty on Sept. 5, 2025. FEKKAS, 36, of Hartsdale, received a 13-year prison term followed by 10 years of supervised release. The White Plains Division handled the case and credited Homeland Security Investigations and the Rockland County District Attorney’s Office for their roles, according to a press release from the U.S. Department of Justice.
Investigation and sting
Authorities say the investigation began when an undercover agent posed online as a 13-year-old and started exchanging messages with a user who identified himself as a high school teacher. According to local reporting, investigators later recovered explicit photos and videos, including material described as having been taken inside a classroom, and they found additional files hidden in a calculator-style app on the defendant’s phone, as reported by News 12 Westchester.
Evidence in court filings
Court documents filed in the Southern District of New York describe online chats in which the defendant requested images and sent sexually explicit content. The filings include technical details about the HideU "calculator" app that was used to conceal files on his device. Prosecutors say FEKKAS coerced a 12-year-old to send a masturbatory video in 2022 and then pressured a 16-year-old over several months in 2022 and 2023 to send explicit images, according to the U.S. Department of Justice.
Prosecutor reaction
“Teachers and others in places of trust who engage in sex crimes have no place in our society,” U.S. Attorney Jay Clayton said in a post shared from the Southern District of New York’s account on X. The office used the post to urge anyone with information about child sexual exploitation to contact Homeland Security Investigations; the full statement appears on the Southern District of New York.
How to report tips
Officials say anyone with information about the sexual exploitation of children should contact Homeland Security Investigations at 1-866-DHS-2423 or submit a tip through the agency’s online form. The HSI tip form is available on the agency’s website and is staffed around the clock for reporting; the online form can be found at Homeland Security Investigations.
The White Plains Division said the prosecution reflects investigators’ focus on online grooming and the protection of children, and it continues to seek additional victims and witnesses. Anyone who believes they were harmed or has relevant information is urged to contact the tip line or local law enforcement.
