A former male nanny in California has been sentenced to 705 years to life, plus an additional two years and eight months after he was found guilty of sexually assaulting 16 young boys and showing a 17th boy pornography with the intent to sexually assault him.

According to the Orange County District Attorney, Matthew Antonio Zakrzewski, 34, of Costa Mesa, California worked as a nanny for families across Southern California and filmed "many" of the assaults on the young boys, who ranged in ages 2 to 12 years old.

The crimes were committed between Jan. 1, 2014 and May 17, 2019, the district attorney said in a release.

Zakrzewski was arrested in 2019 and was originally charged with three felony counts of lewd and lascivious acts with a minor under the age of 14, one felony count of oral copulation of a child under the age of 10 and one felony count of possession of child pornography.

After his initial arrest, additional charges were filed against him as investigators identified additional victims through video evidence and tips from the public.

Ultimately, he was charged with 34 felonies, and was convicted by a jury of all 34.

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Who is Matthew Antonio Zakrzewski?

Zakrzewski described himself as a "manny" and "the original Sitter Buddy" on his website, according to the Orange County District Attorney. He advertised a number of services, including mentorships and big brother relationships, and offered overnight and vacation babysitting.

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How was he caught?

In early May 2019, a Laguna Beach couple who had hired Zakrzewski through one of his babysitting websites reported to the Laguna Beach Police that Zakrzewski had touched their son inappropriately and they were concerned for the safety of their son and potentially other children.

An investigation from Laguna Beach Police Department’s Major Crimes & Intelligence Unit led to the identification of a second seven-year-old victim in Los Angeles, and 10 more boys from across Southern California.