(CNN) Cesar Sayoc, the man accused of sending 16 mail bombs to prominent Democrats and CNN offices, wrote a letter by hand to the judge overseeing his case, saying he never intended for the devices to detonate.

The pipe bombs were "not ever meant to work" or to hurt or harm anyone, Sayoc wrote.

"The intention was to only intimidate & scare," he said in the two-page letter to US District Court Judge Jed Rakoff.

Sayoc pleaded guilty last month to 65 felony counts, including using weapons of mass destruction in an attempted domestic terrorist attack, interstate transport of explosives and illegal mailing of explosives with the intent to kill or injure.

He admitted in court to having mailed 16 explosive devices to a variety of officials -- primarily Democrats, including former Presidents Barack Obama and Bill Clinton and Sens. Cory Booker and Kamala Harris; and major Democratic donors, including George Soros and Tom Steyer -- and to CNN's offices in October 2018.

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